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https://www.physicsforums.com/threads/elastic-collision-finding-ratio-between-m2-and-m1-v2-and-v1.101270/

math

A ball of mass m and a ball of unknown mass M approach each other from opposite directions and have the same speed Vo (but oppositely directed velocities). The ball of M is reduced to rest by the impact, while the ball of mass m has a velocity V1'. What are the ratios a) M / m b) V1' / Vo This is what I've done so far. I ended up with 2 answers, but we're only supposed to have one. Conservation of momentum: mVo + M(-Vo) = mV1' + 0 - divide both sides by mVo, and let x = M / m, y = V1' / Vo ... equation (1'): 1 - x = y Conservation of kinetic energy: 1/2mVo^2 + 1/2M(-Vo)^2 = 1/2mV1'^2 - divide both sides by 1/2mVo^2 ... equation (2'): 1 + x = y^2 equations (1') + (2'): y^2 + y - 2 = 0 (y + 2)(y - 1) = 0 ... y = -2 or 1 Case 1: If y = -2, x = 3 Case 2: If y = 1, x = 0 I dont know how we're supposed to determine which is the correct case. Please help!

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https://supremegrades.com/list-stages-of-production.html

math

a)list stages of production. b) Give,illustrate the realm of ecology d) Differentiate C3 and C4 plants e)List 6 examples of invasive species f)what is ecological efficiency? For a custom-written paper on the above topic, place your order now! What We Offer • On-time delivery guarantee • PhD-level professionals • Automatic plagiarism check • 100% money-back guarantee • 100% Privacy and Confidentiality • High Quality custom-written papers

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https://www.prospects.ac.uk/universities/ucl-university-college-london-3871/mathematics-14730/courses/mathematics-11780

math

Visit the institution website for COVID‑19 updates A minimum of an upper second-class UK Bachelor’s degree in a relevant discipline or an overseas qualification of an equivalent standard. Months of entry The department is home to many internationally renowned mathematicians. Our students go on to pursue successful careers in a variety of settings, primarily as postdoctoral researchers or in the world of finance. Excellent networking opportunities are provided by our central London location and close research links to other London universities. We offer research supervision across a broad range of pure and applied mathematics. General areas of expertise in pure mathematics include analysis, geometry, number theory, and topology. In applied mathematics key areas of activity include fluid dynamics, mathematical modelling, mathematical physics, applied and numerical analysis and financial mathematics. Qualification, course duration and attendance options - full time36 months - part time60 months Course contact details - Dr John Talbot - +44 (0)20 7679 4102

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http://w.astro.berkeley.edu/~echiang/oom/every.html

math

A. How much money can be stolen from a Brinks armored car? In cash? In gold? In diamonds? B. What is the annual income of the Bellagio Casino in Las Vegas? C. What fraction of UC Berkeley's energy needs could be supplied by solar panels on the roof of every campus building? D. Estimate the mass of rubber liberated from car tires each year by cars traveling along the stretch of Highway 80 near Berkeley. E. How many airplanes are in the air at any given instant in time? F. Lead poisoning problem of Sterl's (for homework) G. Swissair flight 111 from New York to Geneva crashed in Halifax Nova Scotia on 2 Sept 1998, killing all 219 on board. As might be expected for a flight with this destination, the lawsuits and settlements have already made this the costliest air disaster in history ($600,000,000). Did this crash represent a significant fluctuation in the number of people in the world who die each day? (i.e., would you notice 2 Sept 1998 on a graph of daily world deaths?) H. Can you read without a flashlight on Pluto? I. How many helium balloons would you need to tie to your chair to start floating away? J. Water usage. (a) How much water (liter/year) is used to grow the food you eat? (b) Estimate the mean annual rainfall (inches) over the planet Earth. K. You inhabit a space station that is 100 m on a side. The station is suddenly struck by debris that opens a hole 10 cm in radius. Do you have enough time to put on your spacesuit? L. A recent television ad campaigned against having casinos built in the Bay area because it would add an estimated "400,000" cars to major highways every day. Is this a good argument?

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https://math.itb.ac.id/2014/03/03/3-mar-2014-dr-yann-palu-from-universite-de-picardie/

math

3 Mar 2014: Dr. Yann Palu from Universite de Picardie A talk by Dr. Yann Palu from Universite de Picardie, Amiens France in our monthly “Mathematics Seminar” with following details. Title: Cluster algebras and representation theory Date: Monday, March 3, 2014 Time: 15.00 -16.00 Place: Ruang Rapat Gedung Matematika Labtek III ITB (ITN, Labtek III Building, Ruang Rapat) Cluster algebras were introduced by Fomin and Zelevisky in their study of total positivity and canonical bases. Starting from an oriented graph, one can define the generators of a cluster algebra by means of an inductive operation called “mutation”. This unusual definition forces cluster algebras to satisfy several interesting properties, such as the Laurent phenomenon and positivity. The combinatorics underlying this mutation procedure turned out to appear in many different areas of mathematics: integrable systems, Poisson geometry, algebraic geometry, and representation theory of algebras. This talk will be an introduction to cluster algebras and an illustration of their basic properties with some small examples. Another talk by same speaker in our bi-weekly “Algebra Seminar” with following details. Title: An introduction to Caldero-Chapoton maps Date: Wednesday, March 5, 2014 Time: 14.30 – 15.30 Place: Ruang Seminar I.2 Gedung Matematika Labtek III ITB (ITB, Labtek III Building, Ruang Seminar I.2) Cluster algebras were introduced by Fomin and Zelevisky. They are defined by giving specific generators, called cluster variables. The Caldero-Chapoton map is an important tool in the theory of categorification of cluster algebras. It gives an “explicit” formula for the cluster variables of a cluster algebra associated with a quiver in terms of the representations of this quiver. The talk will be an introduction to the Caldero-Chapoto map for Jacobi-finite quivers and illustrated with examples.

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https://ro.uow.edu.au/eispapers/2050/

math

The surface area preserving mean curvature flow James McCoy, University of WollongongFollow McCoy, J. A. (2003). The surface area preserving mean curvature flow. The Asian Journal of Mathematics, 7 (1), 7-30. We adopt similar notation to Huisken in [Hu1] and [Hu2]. Let M be an n-dimensional Riemannian manifold. Asian Journal of Mathematics Since March 26, 2014 Science and Technology Studies Commons My Account |

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http://www.teamcrossworld.com/running/2018/01102018-bouldering-firebreather/

math

I meant to do Day 2, but evidently I forgot to take a picture of the book before I left. So I didn’t do it right. Minute 1 – jump rope Minute 2 – kettle bell swing – 26#. For the last rounds I did 120 jump rope and 35 swings. It was supposed to be 1 minute of rope, 1 minute of swings at 35# and then do 30% of that for the EMOM. Oops!

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https://yellowcomic.com/find-the-sum-of-the-measures-of-exterior-angles-one-at-each-vertex-of-an-octagon/

math

A preeminence of polygons is the the amount of the exterior angles constantly equals 360 degrees, however lets prove this for a continual octagon (8-sides). You are watching: Find the sum of the measures of exterior angles one at each vertex of an octagon First we must figure out what every of the interior angles equal. To carry out this we usage the formula: ((n-2)*180)/n where n is the variety of sides the the polygon. In our situation n=8 for an octagon, so we get: ((8-2)*180)/8 => (6*180)/8 => 1080/8 = 135 degrees. This means that each internal angle of the consistent octagon is equal to 135 degrees. Each exterior edge is the supplementary angle to the internal angle at the vertex of the polygon, so in this case each exterior edge is same to 45 degrees. (180 - 135 = 45). Remember that supplementary angles add up come 180 degrees. And since there room 8 exterior angles, we multiply 45 levels * 8 and we acquire 360 degrees. This technique works because that every polygon, as long as you space asked to take it one exterior angle every vertex. upvote 3 Downvote Either i don"t understand your thinking or you are talking bollocks. The internal angles add up tp 1080 in a polygon, ie 135 each. All you have to do is division 360/n, n gift the variety of sides in the polygon I agree with the an initial person. The IS 135!!! Its wrong the prize is 45, every you have to do it take it 360 and divide that by the number of sides (360/n) so lets say the the variety of sides is 6, her equation would certainly be 360/6 which would be and also the answer would certainly be 60. Inspect my mathematics if you don"t think I"m right. This aided me so much thank you Still searching for help? acquire the best answer, fast. ask a inquiry for totally free gain a complimentary answer come a quick problem. Many questions answered within 4 hours. uncover an virtual Tutor now pick an expert and meet online. No packages or subscriptions, pay just for the moment you need. ¢ € £ ¥ ‰ µ · • § ¶ ß ‹ › « » > ≤ ≥ – — ¯ ‾ ¤ ¦ ¨ ¡ ¿ ˆ ˜ ° − ± ÷ ⁄ × ƒ ∫ ∑ ∞ √ ∼ ≅ ≈ ≠ ≡ ∈ ∉ ∋ ∏ ∧ ∨ ¬ ∩ ∪ ∂ ∀ ∃ ∅ ∇ ∗ ∝ ∠ ´ ¸ ª º † ‡ À Á Â Ã Ä Å Æ Ç È É Ê Ë Ì Í Î Ï Ð Ñ Ò Ó Ô Õ Ö Ø Œ Š Ù Ú Û Ü Ý Ÿ Þ à á â ã ä å æ ç è é ê ë ì í î ï ð ñ ò ó ô õ ö ø œ š ù ú û ü ý þ ÿ Α Β Γ Δ Ε Ζ Η Θ Ι Κ Λ Μ Ν Ξ Ο Π Ρ Σ Τ Υ Φ Χ Ψ Ω α β γ δ ε ζ η θ ι κ λ μ ν ξ ο π ρ ς σ τ υ φ χ ψ ω ℵ ϖ ℜ ϒ ℘ ℑ ← ↑ → ↓ ↔ ↵ ⇐ ⇑ ⇒ ⇓ ⇔ ∴ ⊂ ⊃ ⊄ ⊆ ⊇ ⊕ ⊗ ⊥ ⋅ ⌈ ⌉ ⌊ ⌋ 〈 〉 ◊ mathematics Algebra 1 Algebra 2 Calculus Trigonometry Probability Algebra Word trouble Proofs Geometric Proofs ... Math assist Triangle Area one Triangles Volume mathematics Midpoint angles Geometry Word difficulties RELATED QUESTIONSwhat is a bisector geometry answers · 4what is an equation equal of a heat parallel come y=2/3x-4 and goes v the suggest (6,7) answer · 5what room some angles that have the right to be called with one vertex? answers · 2name of a 2 demension number described listed below answers · 6just how to find the distance of the incenter of one equlateral triangle come mid facility of every side? answers · 6 Cristl A.4.9 (1,736) JoAnna S.5.0 (2,338) Allan B.4.9 (191) See much more tutors find an virtual tutor Download our totally free app A connect to the application was sent out to her phone. See more: What Does Wax On Wax Off Mean Ing Of “Wax On, Wax Off”? Wax On, Wax Off Please administer a valid phone number. Google beat app Store acquire to know us discover with united state occupational with united state Download our cost-free app Google beat app Store Let’s save in touch Need an ext help? Learn an ext about just how it works best in business because 2005 Tutors by topic Tutors by ar © 2005 - 2021 yellowcomic.com, Inc, a division of IXL learning - every Rights reserved |

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https://www.sheltonherald.com/news/articleComments/Thanksgiving-fire-safety-13952240.php

math

The Shelton Fire Department is urging the public to keep safety in mind when preparing meals and using candles this Thanksgiving. Statistics from U.S. Fire Administration indicate that Thanksgiving is the peak day for home cooking fires. The average number of home fires on Thanksgiving Day is normally double the average number of fires in homes all other days. Most fires that result during cooking can be avoided by paying attention and being organized. To prevent a fire or injury and stay safe when cooking and celebrating Thanksgiving, follow these simple rules: \u00b7\u00a0 \u00a0 \u00a0 \u00a0Stay in the kitchen when you are frying, grilling, or broiling food. If you must leave the home for even a short period of time, turn off the stove or oven. \u00b7\u00a0 \u00a0 \u00a0 \u00a0If you are simmering, baking, boiling, or roasting food, check it regularly and remain in the home while food is cooking. Use a timer to remind you that the stove or oven is on. \u00b7\u00a0 \u00a0 \u00a0 \u00a0Stay alert. Don\u2019t cook if you are sleepy, have been drinking alcohol or have taken medicine that makes you drowsy. \u00b7\u00a0 \u00a0 \u00a0 \u00a0Make your cooking area safe. Move things that can burn away from the stove. Keep things that burn \u2013 pot holders, oven mitts, paper or plastic - off your stovetop. \u00b7\u00a0 \u00a0 \u00a0 \u00a0Turn pot handles toward the back so they can\u2019t be bumped. \u00b7\u00a0 \u00a0 \u00a0 \u00a0Don\u2019t store things that can burn in an oven, microwave, or toaster oven. \u00b7\u00a0 \u00a0 \u00a0 \u00a0Clean food and grease off burners, stovetops, and ovens. \u00b7\u00a0 \u00a0 \u00a0 \u00a0Wear clothing with sleeves that are short, close fitting, or tightly rolled up. \u00b7\u00a0 \u00a0 \u00a0 \u00a0Always keep an oven mitt and lid nearby when you're cooking. If a small grease fire starts in a pan, put on an oven mitt and smother the flames by carefully sliding the lid over the pan. Turn off the burner. Don't remove the lid until it is completely cool. \u00b7\u00a0 \u00a0 \u00a0 \u00a0If there is an oven fire, turn off the heat and keep the door closed to prevent flames from burning you and your clothing. Have the oven serviced before you use it again. \u00b7\u00a0 \u00a0 \u00a0 \u00a0Use turkey fryers outdoors, away from the home and deck. Always monitor oil temperature. Use caution to not overfill or spill hot oil. \u00b7\u00a0 \u00a0 \u00a0 \u00a0Keep children away from the stove. The stove will be hot and kids should stay 3 feet away. Don\u2019t forget about fire dangers posed by lit candles. \u00b7\u00a0 \u00a0 \u00a0 \u00a0Flameless \u201ccandles\u201d, such as battery powered are always preferred for safety. \u00b7\u00a0 \u00a0 \u00a0 \u00a0Flame lit candles should be in a safe location that is kept free of combustible surroundings. Consider where combustible items might be placed and where candles could be knocked over and where they could be forgotten about over time. \u00b7\u00a0 \u00a0 \u00a0 \u00a0Never leave children alone in room with a lit a candle.

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CC-MAIN-2021-31

https://www.middleweb.com/50436/my-students-struggle-to-solve-basic-equations/

math

My Students Struggle to Solve Basic Equations A MiddleWeb Blog I actually wrote an article about the problem in 2021: Refreshing Students’ Equation Solving Skills. Since then I have been purposefully trying to help students get better at solving equations. I’ve done things like having students keep their work neater so they don’t make careless errors, drawing a line by the equal sign to help them visualize the equality, and in general just trying to get them to write things down. Yet my students each year still continue to struggle in this area, and since solving an equation is the foundation that most higher math concepts build off of, we’ll continue to try to improve. Pinpointing problem areas I realized I was going to have to be more strategic if I was going to help my students. I needed to know what they are specifically having trouble understanding. So I picked two problems (they were based on 6th and 7th grade standards in our state) for my 11th graders to work. MA19.6.19 Write and solve an equation in the form of x+p=q or px=q for cases in which p, q, and x are all non-negative rational numbers to solve real-world and mathematical problems. MA19.7.9a Solve word problems leading to equations of the form px+q=r and p(x+q)=r, where p, q, and r are specific rational numbers. Solve equations of these forms fluently. Compare an algebraic solution to an arithmetic solution, identifying the sequence of the operations used in each approach. I had my students come up to my desk one at a time. I presented them with the problems and a four-function calculator. They worked a problem and often talked out loud about what they were thinking as they were working. I didn’t ask them to, that was just a bonus! Here are the two problems: 20 – 7x = 6x -6 2/3b + 7 = -1 I listened as they worked. Then I took the Post-it notes they had worked their problems on and really studied their work. In fact, I often rewrote what the student wrote so I could really understand their thinking. That helped me so much. I have always struggled trying to determine what students were thinking. By rewriting their work, I was able to gain more insight. I then sorted the Post-it notes according to the type of error each student made. I have listed the categories below. ►Confused by Fractions Not surprisingly, the problem with the fraction was missed much more than the one without. A few students said that they could not begin the problem because it had a fraction in it, and no amount of encouragement could persuade them to try it. Some students stopped after subtracting both sides by 7 because they simply didn’t know what to do with 2/3, so their answer was -8. Some students multiplied both sides by two thirds instead of multiplying by the reciprocal; their answer was -16/3. One student subtracted 2/3 from both sides, after they subtracted 7 from both sides. ►Combined Unlike Terms Students combined 20 with -7x to get 13x, while 6x-6 was combined to get x. And others combined 2/3b with 7 to get 14/3b. ►Moved or Lost the Equal Sign If students subtracted so that they had a zero on one side of the equation, often the equal sign would just disappear. Sometimes the equal sign would never be seen in the students’ work at all. What does this all mean? In the broadest sense it means that students who struggle to solve a 6th or 7th grade level equation will definitely struggle to solve quadratic, exponential, or logarithmic equations that are part of the Algebra 2 course of study. More time has to be spent fortifying students’ ability in this area. Realizing that this was necessary, we allowed for a few weeks at the beginning of the year to refresh students on solving equations. It wasn’t enough. Now I’m thinking it would be better to spiral in problems and continue working on it all year long. Specifically, I think there are some fundamental skills related to solving equations that students are lacking. Maybe lacking is not the right word; maybe they have the skills but are unable to always apply them correctly or at the right time. What are students not understanding? I think the problem they have with fractions indicates they don’t understand reciprocals. Students know that 2/3 is literally 2 divided by 3; so they mistakenly think they should multiply both sides by 2/3. To complicate matters, they are afraid of fractions. They will skip a whole problem if it has a fraction in it. Why are students still combining unlike terms? I am at a loss. We model constantly the correct way to combine like terms. I think sometimes, if students don’t know what to do, they think they should try anything. I heard a lot of “I know I’m supposed to do something here…” The moving or missing equal sign is about more than sloppy work. It’s a lack of understanding about equivalence. They haven’t really learned what the equal sign signifies. What to do about it? These are my first thoughts about how to help students solve equations. Model correct vocabulary, It’s not 7x; it’s 7 multiplied by x. It also might be helpful to say one x, as opposed to x. That’s tedious, but I don’t think all students understand the invisible “one” there. Also, do students know that multiplying by 3/2 will yield the same answer as dividing by 2/3? Make sure students are clear on the definition of solving an equation. To solve an equation means to find all numbers that make the equation true. Source Help students understand equivalence. Make it mandatory that students plug their solution back in after solving the problem. They will literally be able to see that the correct answer is one that makes the equation true. That will drive home the meaning of the equal sign and help them understand the definition of equivalence. Be more intentional when teaching students how to “undo” multiplication, division, etc. Explicitly state when to subtract 2x from each side and when to divide both sides by 2. I also need to diagnose problems sooner. I need to study students’ work in the early weeks of our time together and see what they know and what they don’t know about solving equations. Much of the problem rests with my assumption that when students arrive in my class, they have mastered solving equations – when they haven’t. Going forward I am going to assume that my students need some coaching and practice and one-on-one help to be proficient at solving equations. I can’t fall back on the fact that I work a lot of equations on the board. When students watch their teacher solve equations on the board, they don’t know what they don’t know. It’s easy to watch someone do something and think “that’s easy; I can do that.” I plan to talk with other teachers in my department and see what they suggest. I also want to check with some of our middle school teachers to see if they have any suggestions. And thanks in advance for sharing any ideas you might have in the comments below.

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CC-MAIN-2024-18

https://psychology.fandom.com/wiki/Error_of_measurement

math

Individual differences | Methods | Statistics | Clinical | Educational | Industrial | Professional items | World psychology | The error of measurement is the observed differences in obtained scores due to chance variance. The standard error of measurement or estimation is the estimated standard deviation of the error in that method. Specifically, it estimates the standard deviation of the difference between the measured or estimated values and the true values. Notice that the true value of the standard deviation is usually unknown and the use of the term standard error carries with it the idea that an estimate of this unknown quantity is being used. It also carries with it the idea that it measures not the standard deviation of the estimate itself but the standard deviation of the error in the estimate, and these are very different. In applications where a standard error is used, it would be good to be able to take proper account of the fact that the standard error is only an estimate. Unfortunately this is not often possible and it may then be better to use an approach that avoids using a standard error, for example by using maximum likelihood or a more formal approach to deriving confidence intervals. One well-known case where a proper allowance can be made arises where the Student's t-distribution is used to provide a confidence interval for an estimated mean or difference of means. In other cases, the standard error may usefully be used to provide an indication of the size of the uncertainty, but its formal or semi-formal use to provide confidence intervals or tests should be avoided unless the sample size is at least moderately large. Here "large enough" would depend on the particular quantities being analysed. Standard error of the mean The standard error of the mean (SEM), an unbiased estimate of expected error in the sample estimate of a population mean, is the sample estimate of the population standard deviation (sample standard deviation) divided by the square root of the sample size (assuming statistical independence of the values in the sample): - s is the sample standard deviation (i.e. the sample based estimate of the standard deviation of the population), and - n is the size (number of items) of the sample. A practical result: Decreasing the uncertainty in your mean value estimate by a factor of two requires that you acquire four times as many samples. Worse, decreasing standard error by a factor of ten requires a hundred times as many samples. This estimate may be compared with the formula for the true standard deviation of the mean: - σ is the standard deviation of the population. Note: Standard error may also be defined as the standard deviation of the residual error term. (Kenney and Keeping, p. 187; Zwillinger 1995, p. 626) If values of the measured quantity A are not statistically independent but have been obtained from known locations in parameter space x, an unbiased estimate of error in the mean may be obtained by multiplying the standard error above by the square root of (1+(n-1)ρ)/(1-ρ), where sample bias coefficient ρ is the average of the autocorrelation-coefficient ρAA[Δx] value (a quantity between -1 and 1) for all sample point pairs. Assumptions and usage If the data are assumed to be normally distributed, quantiles of the normal distribution and the sample mean and standard error can be used to calculate confidence intervals for the mean. The following expressions can be used to calculate the upper and lower 95% confidence limits, where x is equal to the sample mean, s is equal to the standard error for the sample mean, and 1.96 is the .975 quantile of the normal distribution. - Upper 95% Limit = - Lower 95% Limit = In particular, the standard error of a sample statistic (such as sample mean) is the estimated standard deviation of the error in the process by which it was generated. In other words, it is the standard deviation of the sampling distribution of the sample statistic. The notation for standard error can be any one of , (for standard error of measurement or mean), or . Standard errors provide simple measures of uncertainty in a value and are often used because: - If the standard error of several individual quantities is known then the standard error of some function of the quantities can be easily calculated in many cases; - Where the probability distribution of the value is known, it can be used to calculate an exact confidence interval; and - Where the probability distribution is unknown, relationships like Chebyshev’s or the Vysochanskiï-Petunin inequality can be used to calculate a conservative confidence interval - As the sample size tends to infinity the central limit theorem guarantees that the sampling distribution of the mean is asymptotically normal. - Consistency (measurement) - Least squares - Observational error - Sample mean and sample covariance - Scoring (testing) - Statistical estimation - Statistical measurement - Test bias - Test reliability - Test scores Survival function - Kaplan-Meier - Logrank test - Failure rate - Proportional hazards models |This page uses Creative Commons Licensed content from Wikipedia (view authors).|

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CC-MAIN-2022-05

http://www.1point3acres.com/bbs/thread-111659-1-1.html

math

2014(10-12月) 码农类 硕士 全职@EPIC - 网上海投 - 技术电面 |Other 1. mountain:Given a M * N matrix, if the element in thematrix is larger than other 8 elements who stay around it, then named thatelement be mountain point. Print all the mountain points. 2.add two numbers represented by two arrays. [1, 2, 3, 4, 5] + [7, 2, 5] = [1, 3, 0, 7, 0] 3.Find all the possible passwords, given the length of the password and that it is a well ordered number (159 is well-ordered as 1<5<9) 4. Colorful number: Determine whether a number is colorful or not. 263 is a colorful number because (2,6,3,2x6,6x3,2x3x6) are all different whereas 236 is not because (2,3,6,2x3,3x6,2x3x6) have 6 twice. So take all consecutive subsets of digits, take their product and ensure all the products are different

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CC-MAIN-2017-17

http://onlivetalk.com/sampling-error/sampling-error-describes.php

math

Sampling Error Describes That or any confidence level indicates the number of times a theoretical infinite number of samples, of a given size and a given result, would come within sampling error of the Martin A. Why? For this reason, eliminating bias should be the number one priority of all researchers. have a peek here Steel M. Show Full Article Related Simple Random Sample What Is a Simple Random Sample? Random sampling is used precisely to ensure a truly representative sample from which to draw conclusions, in which the same results would be arrived at if one had included the entirety Accessed 2008-01-08. https://en.wikipedia.org/wiki/Sampling_error Non Sampling Error Non-sampling error can include (but is not limited to): Coverage error: this occurs when a unit in the sample is incorrectly excluded or included, or is duplicated in the sample (e.g. Powell Vicki Clarke Wiki New Zealand Year added 2016 2015 2014 2013 2012 2011 2010 2009 2008 2006 2003 1999 1998 1995 201 Clear all fields Add a teaching resource Walsh Jn Te Aomihia Walker Team Solutions The University of Auckland Tim Harford University of Cambridge University of Virginia V. Dalrymple Dru Rose E. And a result computed at the 90 percent confidence level has a smaller error margin than a result computed at 95 percent confidence. Gibbs G. For example, if one measures the height of a thousand individuals from a country of one million, the average height of the thousand is typically not the same as the average How To Calculate Sampling Error About.com About Education Sociology . . . Since sampling is typically done to determine the characteristics of a whole population, the difference between the sample and population values is considered a sampling error. Exact measurement of sampling error In order to understand it, you have to be able and willing to do a thought experiment. And in some cases we'll report the confidence level at which a result is statistically significant. https://en.wikipedia.org/wiki/Sampling_error The sample may be representative and not have much non-sampling error at all, but there is sampling error. Every sample design will generate a certain amount of random error.Bias, on the other hand, is more serious because the pattern of errors is loaded in one direction or another and How To Reduce Sampling Error Rosling H. Please enter a valid email address. If we had a sampling distribution, we would be able to predict the 68, 95 and 99% confidence intervals for where the population parameter should be! Sampling Error Formula About Dr Nic I love to teach just about anything. navigate here Wilcox Marion Steel Mathematics & Statistics Facilitator Mathematics and Statistics Facilitators MathsBitsNotebook.com Michael Shadbolt Ministry of Education N. Bookmark the permalink. If additional data is gathered (other things remaining constant) then comparison across time periods may be possible. Random Sampling Error Definition Please try again. Sampling Error Ap Gov Accessed 2008-01-08. Ritchie H. Sampling error gives us some idea of the precision of our statistical estimate. And there are now two videos to go with the diagram, to help explain sampling error and non-sampling error. Sampling always refers to a procedure of gathering data from a small aggregation of individuals that is purportedly representative of a larger grouping which must in principle be capable of being Defining Error and Bias In survey research, error can be defined as any difference between the average values that were obtained through a study and the true average values of the Sampling Error Refers To Quizlet Thank you,,for signing up! Miyahara M. The greater your sample size, the smaller the standard error. Hockly J. this contact form Smith David Knight Department of Statistics Dr D. M. If you measure the entire population and calculate a value like a mean or average, we don't refer to this as a statistic, we call it a parameter of the population. Cunliffe R. Since sampling is typically done to determine the characteristics of a whole population, the difference between the sample and population values is considered a sampling error. Exact measurement of sampling error So why do we even talk about a sampling distribution?

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http://www.chegg.com/homework-help/questions-and-answers/engine-model-rocket-accelerates-rocket-vertically-upward-20-s-follows-t-0-rocket-s-speed-z-q946563

math

average acceleration and instantaneous acceleration problems 0 pts endedThis question is closed. No points were awarded. The engine of a model rocket accelerates the rocket vertically upward for 2.0 s as follows: at t = 0, the rocket's speed is zero; at t = 1.0 s, its speed is 5.0 m/s; and at t = 2.0 s, its speed is 15 m/s. Plot a velocity vs. time graph for this motion, and use the graph to determine each of the following. (a) the average acceleration during the 2.0 s interval (b) the instantaneous acceleration of the rocket at t = 1.5 s

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https://www.jiskha.com/display.cgi?id=1318111676

math

posted by Mishaka . What is the limit of the function as x approaches infinity? 4x^4 - 4^x Would the limit be positive infinity or negative infinity? exponentials grow much faster than powers. note that the slope of x^4 = 4x^3 (a lower power), while the slope of 4^x is basically 4^x still. For example, 10^4 = 10000 but 4^10 =~ 1,000,000 and it gets worse the farther out you go. So, since you're subtracting a huge number from a smaller number, the limit is -oo.

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https://www.gambln.com/betting/ten-reasons-why-you-should-never-play-these-six-lotto-numbers/

math

You will never believe this, but it is a known fact amongst many lottery players that the combination of numbers: one two three four five six is a definite losing combination. Are you surprised? Although many wise, yet inexperienced lotto players, mathematicians believe that no matter which six numbers you choose/predict in a lotto game, they all have equal chance of being the winning combination. Well, so they believe, but the question remains, are they right? No, they’re not. Once you actually study the statistics and analyse each lottery game’s drawing outcomes, and not only in your country alone, but world-wide since as early as the year ninety fifty five, you will confidently be able to confirm all logical probabilities by applying one plain and simple rule. The most probable will happen most frequently, and the least probable will happen less frequently. Therefore, if you always play the probabilities you stand a much better chance of winning at a lotto game. For example if you use a pattern of numbers which has only won five % of lottery games, then you can be certain of a ninety five % chance of losing. Or if you chose a combination of six numbers which has never in the history of any lottery game been chosen, then plain common sense will tell you that you have a zero chance at winning. Surely those mathematicians who believe the opposite to be true should listen to their common sense instead of mathematical calculations and realise their calculations and beliefs are totally absurd when it comes to a lottery game. If you really want to win at a lottery game one day, take note of these ten reasons why you should never play these six lotto numbers: 1. One number combination 2. Sequential numbers 3. Pattern betting 4. Bordering Numbers 5. Calendar Figures 6. All numbers are low, and not half only 7. Tail end of a bell bend 8. Twenty thousand tickets sold at each lotto draw 9. Not a well-adjusted game 10. Falls short of the seventy % of the possible range of sums So now you know. If you are playing these numbers, try and avoid them the next time you get your lotto ticket from http://luckynumbers.co.za/

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https://stargradeessays.com/create-a-5-pages-page-paper-that-discusses-the-design-of-mechanical-structures/

math

Create a 5 pages page paper that discusses the design of mechanical structures. The principal aim of this lab activity was to carry out the experimental deflection measurements on statically determinate and later statically indeterminate beams. After the exercise, a comparison of the data obtained, and the beam theory predictions are to be made. Besides, the lab experiment aims at verifying the principle of superposition for beam deflection. When a beam is bent, it ends up taking various shapes. These different forms may be represented on an x –y graph where the origin is located at the left end of the beam. At any distanced meters from the left end, the beam will have a deflection y and a gradient given by the differential formulae dy/dx. The equation relating to the bending moment and the radius of curvature of a beam is given by the equations M/I=E/R, where the parameters M represents the bending moment, I represents the second moment of area about the centroid, E represents the modulus of elasticity, and R gives the radius of curvature. After rearranging the equation, the following is obtained: I/R=M/E. The figure below illustrates the radius of curvature that is usually defined as the radius of a circle having a tangent similar to the point on the x-y when plotted on a graph (Callister & Rethwisch, 2007). When a simply supported beam holding a central concentrated load is deflected, its deflection varies when several changes occur. Among them include, change in the Load, change in Span, variation in the Breadth of cross-section, and alteration in the Depth of cross-section. In simple terms, the relationship in all these parameters can be given by the formulae: Hi there! Click one of our representatives below and we will get back to you as soon as possible.

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http://dangerousidea.blogspot.com/2012/10/the-ending-to-my-infidels-paper-on.html

math

The paper is here. If my foregoing discussion is correct, opponents of, say, the resurrection of Jesus cannot appeal to a general theory of probability to prove that anyone who accepts the resurrection is being irrational. It is also a consequence that different people can reasonably expected to have different credence functions with respect to Christian (and other) miracle claims. If you want to convince some people that Christ was resurrected, you have a much heavier burden of proof than you have in convincing others. It must be noted that there is no way, on the model I have presented, to show that everyone who denies the Resurrection is irrational, or engaged in bad faith. Of course, one can still believe that unbelievers disbelieve because of "sin" or "suppressing the truth," or what have you. But given the legitimate differences that can exist concerning the antecedent probability of the miraculous, I don't see how such charges can be defended. So the lesson here, I think, is that both apologetics and anti-apologetics should be engaged in persuasion, not coercion, and that the attempt to ground irrationality charges against one's opponents is a misguided enterprise.

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http://deposit.d-nb.de/cgi-bin/dokserv?id=3554080&prov=M&dok_var=1&dok_ext=htm

math

This book covers the modular invariant theory of finite groups, the case when the characteristic of the field divides the order of the group, a theory that is more complicated than the study of the classical non-modular case. Largely self-contained, the book develops the theory from its origins up to modern results. It explores many examples, illustrating the theory and its contrast with the better understood non-modular setting. It details techniques for the computation of invariants for many modular representations of finite groups, especially the case of the cyclic group of prime order. It includes detailed examples of many topics as well as a quick survey of the elements of algebraic geometry and commutative algebra as they apply to invariant theory. The book is aimed at both graduate students and researchers—an introduction to many important topics in modern algebra within a concrete setting for the former, an exploration of a fascinating subfield of algebraic geometry for the latter.

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http://math.rutgers.edu/academics/graduate-program/course-descriptions/1017-640-503-theory-of-functions-of-a-complex-variable-I

math

Complex Analysis, Elias M. Stein and Rami Shakarchi, Princeton Lectures in Analysis II, Princeton University Press (April 7, 2003). ISBN-10: 0691113858 Acquaintance with analytic arguments at the level of Rudin's Principles of Mathematical Analysis is necessary. Some knowledge of algebra and point-set topology is useful. The study of differentiable functions of one complex variable has applications and extensions to many other areas of mathematics, so that it is a basic tool in diverse situations. Topics to be covered include: differentiability of complex functions, complex integration and Cauchy's theorem, series expansions, calculus of residues, maximal principle, conformal mapping, analytic continuation and time permitting, the Prime Number Theorem. Note: A Problem Session for 503 will be held on Wednesdays, 10:00am-11:40am in room 425 for the Fall semester. There is no need to register for the Problem Sessions.

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https://yonsei.elsevierpure.com/en/publications/a-construction-of-odd-length-generators-for-optimal-families-of-p

math

In this paper, we give a construction of optimal families of N-ary perfect sequences of period N2, where N is a positive odd integer. For this, we re-define perfect generators and optimal generators of any length N which were originally defined only for odd prime lengths by Park, Song, Kim, and Golomb in 2016, but investigate the necessary and sufficient condition for these generators for arbitrary length N. Based on this, we propose a construction of odd length optimal generators by using odd prime length optimal generators. For a fixed odd integer N and its odd prime factor p, the proposed construction guarantees at least (N/p)p-1φ(N/p)φ(p)φ(p-1)/φ(N)2 inequivalent optimal generators of length N in the sense of constant multiples, cyclic shifts, and/or decimations. Here, φ (·) is Euler's totient function. From an optimal generator one can construct lots of different N-ary optimal families of period N2, all of which contain pmin-1 perfect sequences, where pmin is the least positive prime factor of N. Bibliographical notePublisher Copyright: © 2018 IEEE. All Science Journal Classification (ASJC) codes - Information Systems - Computer Science Applications - Library and Information Sciences

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https://www.datasheets.com/tools/ohm-s-law-calculator

math

Accurate Ohm's Law Calculator | Voltage, Current, Resistance & Power | Free Online Tool Ohm's Law Calculator is an online tool that calculates the relationship between electric current, voltage, and resistance, based on Ohm's Law. It is a useful tool for electricians, engineers, and students who want to calculate the value of any of the three variables and solve problems related to electrical circuits. Using the Ohm's Law Calculator is very easy. There are three input fields where you can enter the values of the two variables you know, and the calculator will automatically calculate the third variable. The three variables are: - Voltage (V): The electrical potential difference between two points in a circuit, measured in volts (V). - Current (I): The flow of electric charge through a conductor, measured in amperes (A). - Resistance (R): The property of a material that opposes the flow of electric current, measured in ohms (Ω). To use the Ohm's Law Calculator, follow these simple steps: - Choose the variable you want to calculate (voltage, current, or resistance). - Enter the values of the two known variables in the input fields. - Click on the "Calculate" button, and the calculator will display the result in the third input field. The main advantage of using the Ohm's Law Calculator is its speed and accuracy. Instead of manually calculating the value of the unknown variable using Ohm's Law formula (V = IR, I = V/R, or R = V/I), you can get an instant result with just a few clicks. This saves time and reduces the chance of making calculation errors. Additionally, the calculator is user-friendly and provides a clear interface for easy navigation. Moreover, the Ohm's Law Calculator also includes a graphical representation of the circuit and its values, making it easier to understand the relationship between the variables. The calculator also allows you to switch between different units of measurement, such as volts, millivolts, kilovolts, amperes, milliamperes, kiloamperes, ohms, kiloohms, and megohms, which makes it more versatile and convenient to use for a wide range of applications. In conclusion, the Ohm's Law Calculator is a useful tool for anyone who deals with electrical circuits and needs to calculate the values of voltage, current, and resistance quickly and accurately. Its user-friendly interface, graphical representation, and the ability to switch between different units of measurement make it an essential tool for electricians, engineers, and students. It is believed that these calculations are accurate, but not guaranteed. Use at your own risk!

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https://www.jiskha.com/display.cgi?id=1357345285

math

posted by HELLO A forest is burning in a valley. If the fire burns for h hours, the cost of the lost timber is 1000h dollars. They estimate that x firefighters can stop the fire in 3600/x hours. The cost for each firefighter is $20 (transportation)plus $25 per hour (salary/ food). A. Let C be the cost of the fire. C will depend on both h and x . Give a formula for C in terms of x and h. B. Give a formula that relates x and h. C. How may firefighters should be used if the cost C of the fire is to be minimized? so, given x firefighters, h = 3600/x C(h,x) = 1000h + 20x + 25hx C(x) = 1000(3600/x) + 20x + 25(3600/x)x = 3600000/x + 20x + 25*3600 dC/dx = -3600000/x^2 + 20 dC/dx=0 when x^2 = 180000 x = 424 since C" > 0, it's a minimum. x=180000^1/2 (approx. 424.26) to justify it do d2c/dx^2 sub in your answer which is positive, therefore the point is a minimum. A. The cost of the timber lost = 1000 h The cost to have x firemen is x(25 h +20) The time to stop the fire is t= 3600/x C= 1000 h + x(25h + 20) B. Set h = t H = 3600/x C. Substitute for x in cost equation C= 1000 h + x(25h + 20) = 1000*3600/x + x(25*3600/x +20) = 3.6*10^6/x + 25*3600 +20x Take dC/dx and set the result equal to zero DC/dx = 0= -3.6*10^6/x^2 +20. ----> x =sqrt(1.8*10^5) = 424

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http://boffin-solutions.com/secondary-imbibition-in-core-plug/

math

A water-wet vertical core plug initially saturated with oil is subjected to water injection from the bottom end, through a porous frit disc fully saturated with water and impermeable to oil. The core plug has a diameter of 1.0 inch and a length of 1.5 inch. Its absolute permeability and porosity values are 100 mD and 0.25, respectively. The residual water and oil saturations are Scw = 0.2 and Sor = 0.3, respectively; the initial water saturation of the plug is 0.22. The system is at room temperature, and the density and viscosity values of the water and oil are ρw = 1.0 g/cc and ηw = 1.0 cP, and ρo = 0.85 g/cc and ηo = 3.0 cP, respectively. The frit disc is 0.125 inch thick and has a permeability of 500 mD. This two-dimensional model employs Cartesian coordinates. The water saturation as function of the capillary pressure between the two liquids is given by a synthetic curve as shown in Figure 2. The relative permeability curves shown in Figure 3 are described by Corey relationships with Corey exponents of 5.0 and 2.5 for water and oil, respectively, while the end-point relative permeability values are krw_or = 0.25 and kro_cw = 0.7. Gravity effects are included in the model. Water injection occurs through the bottom boundary. The injection velocity is increased from zero at t = 0 to Vin = 13.2 micron/s in one minute, after which it is maintained constant (the value of Vin corresponds to an injection flow rate of five pore volumes per hour, for this two-dimensional geometry). The average water saturation Sw in the core plug as a function of time is plotted in Figure 4, while the distribution of Sw in the sample at selected time steps is shown through the Movie.

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CC-MAIN-2019-26

https://www.physicsforums.com/threads/double-integrals-with-ibp.759767/

math

1. The problem statement, all variables and given/known data ∫∫[ye^(-xy)]dA R=[0,2]×[0,3] evaluate the integral. 2. Relevant equations 3. The attempt at a solution So I started with some algebra changing the integral to ∫(e^-x)[∫ye^-ydy]dx I evaluated the y portion first because its more difficult to deal with and wanted to get it out of the way. I ended up integrating by parts with: U=y dv=e^-x Dy=dy v=-e^-x and got -ye^(-y) - ∫-e^(-y)dy on the interval [0,3] and got -4e^(-3) + 1 This is now a constant, pulled it out of the x integral leaving: (-4e^(-3) +1)∫e^(-x)dx The final integral I evaluated as: -e^(-x) on [0,2] gives -e^(-2) + e^0 and this is multiplied by the previous number to give: 4e^(-6)-4e^(-3)-e^(-2)+1 Using a calculator to approximate I get a value of 0.692468 The answer in the book is .5e^(-6) + (5\2) which is approximated by a calculator as 2.5012394 I'm doing something wrong and I am wondering if there is a rule I forgot, do I need to integrate by x first and then y?

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http://www.chegg.com/homework-help/questions-and-answers/solve-node-voltages-use-appropriate-computer-tool-eg-mathcad-matlab-maple-calculators-etc--q1245771

math

Show transcribed image text Solve for the node voltages. Use an appropriate computer tool (e.g.. Mathcad, Matlab. Maple, some calculators, etc.). See the instructor if you have questions about what is appropriate. Calculate the power that each source produces, and calculate the power that the each resistor uses. Check power balance: total source power production equals total resistor power use. The sources may represent OC generators that are converting mechanical energy to electrical form, while the resistors are converting electrical energy to heat (or light and heat in the case of a lamp). The smaller resistors are representing the resistance of the wires used to connect the sources to the loads, and the larger resistors are representing the loads.

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https://kazakhsteppe.com/solution-421

math

Math problems to solve Here, we debate how Math problems to solve can help students learn Algebra. Our website can help me with math work. The Best Math problems to solve Apps can be a great way to help students with their algebra. Let's try the best Math problems to solve. So before you choose any of the websites on this list, it’s a good idea to do some research on them and make sure they are a good fit for your child’s needs. Many sites have free trial periods that allow you to try out their services without paying anything at all, which is great because it allows you to see if it’s right for your child before you have to commit to anything. Some sites also offer free trial periods for certain plans, so be sure to check those out as well. In addition, make sure that the site has an easy-to-use interface and that there are no hidden fees or charges. And lastly, make sure that the site offers a 24/7 support line so that your child can get help whenever they need it. Expression is a math word that means to write something as an equation. For example, 2 + 3 would be written as (2+3). There are many types of expressions in math. One type of expression is an equation. An equation is just a math word that means to write something as an equation. For example, 2 + 3 would be written as (2+3). Another type of expression is an equation with variables. In this type of expression, the variables replace the numbers in the equation. For example, x = 2 + 3 would be written as x = (2+3). A third type of expression is a variable in an equation. In this type of expression, the variable stands for one of the numbers in the equation. For example, x = 2 + 3 would be written as x = (2+3). A fourth type of expression is called a fraction in which you divide something by another thing or number. Fractions are written like regular numbers but with a '/' symbol before the number. For example, 4/5 would be written as 4/5 or 4 5/100. Anything that can be written as a number can also be used in an addition problem. This means that any number or group of numbers can be added together to solve an addition problem. For example: 1 + 1 = 2, 2 + 1 = 3, and 5 - The partial fraction decomposition solver is used to solve the boundary value problem of a partial fraction expression. This method is widely used in scientific, engineering, and finance fields. This solver works in two steps: The first step requires finding the roots of the following equation. br>The second step requires solving for one variable at a time. br>For each root, use the formula for that variable to obtain an approximate value for the remaining variables. br>Then combine these approximate values using an algorithm to obtain a final answer. br>For more information on solving boundary value problems using partial fraction decomposition, see Partial fraction decomposition Solver. To solve a trinomial, first find the coefficients of all of the terms in the expression. In this example, we have ("3x + 2"). Now you can start solving for each variable one at a time using algebraic equations. For example, if you know that x = 0, y = 9 and z = -2 then you can solve for y with an equation like "y = (0)(9)/(-2)" After you've figured out all of the variables, use addition or subtraction to combine them into one final answer.

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http://www.brightstorm.com/math/algebra-2/exponents-2/scientific-notation-2-problem-3/

math

Scientific notation can make our life easier when we are multiplying really big and really small numbers. So what we want to do in this case is to rewrite all these numbers using scientific notation. So figure out where we want our decimal spot and then count the number of digits we're moving our decimals over. So this is going to be 9, remember that a number has to be between 1 and 10 and now we're moving 1, 2, 3, 4, 5 so this is just 9 times 10 to the 5th. So then times going across we want the decimal to be after the 4 because remember that our leading term that a has to be between 1 and 10, and then count the number of decimals we're moving 1, 2, 3, 4, 5, we're moving backwards so it's going to be a negative. Same thing for the bottom we end up with 2; 1, 2, 3, 4, 5, 6, it's going to be a positive 6 because we're moving to a big number and then our last one is 1 times and then 1, 2, 3, 4, 5, 6, 7, 8 and that is going to be a negative. So what we have here are a number of things that we're multiplying together, but remember we can rearrange it when we're multiplying and dividing and then combine like terms. So with a little bit of rearranging I'm going to get all my standard numbers to one side and all my powers of 10 to the other, so what we end up with is this is equal to 9 times 4 times 10 to the 5th times 10 to the -5th over 2 times 1 times 10 to the 6th times 10 to the -8. So what I'm going to do is first just focus on our powers of 10. Remember when we are multiplying powers, we can just add our exponents, so what we really end up with in the top is just 10 to the zero or just 1, these just cancel out and what we have down here adding these is just going to be 10 to the -2. In the top we have 36 divide by 2 is 18, so what we really have then is 18 over 10 to the -2. Using our rules of exponents remember that a negative in the denominator becomes a positive if we flip it up, so this becomes 18 times 10² and the last thing to remember is that our first term has to be between 1 and 10. This is 18 so what I need to do is really move my decimal place over one unit so what I end up with is 1.8 times 10 to the third. So what started out with as a pretty ugly multiplication, by rewriting everything in scientific notation and then just using what we know about combining like terms and laws of exponents, we were able to simplify it up quite easily.

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CC-MAIN-2015-48

https://books.google.com/books?id=u0U3AAAAIAAJ&q=n-vector&source=gbs_word_cloud_r&hl=en

math

47 pages matching n-vector in this book Results 1-3 of 47 What people are saying - Write a review We haven't found any reviews in the usual places. activity amount assert assignment problem assume basic solution called chapter choose column computation condition consider convex combination convex cone convex polytope COROLLARY corresponding define definition demand denote dual problem duality theorem economic edges entries equation example exchange matrix exists feasible vector finite cone flow follows Fundamental Theorem Game Theory give given hence independent subset inequalities integers intensity vector irreducible subsets LEMMA LIBRARIES STANFORD UNIVERSITY linear combination linear model linear programming linear programming problem linear space matrix game maximize maximum minimize mixed strategies n-vector nodes non-negative solution Note optimal strategies path pay-off matrix play positive precisely productive PROOF prove pure strategies rank real numbers saddle point saiavaan satisfy semi-positive solution sets of optimal simplex method solve STANFORD UNIVERSITY LIBRARIES strategy for player strategy x supply suppose symmetric game tableau theory unique verifies zero

s3://commoncrawl/crawl-data/CC-MAIN-2015-32/segments/1438042989018.40/warc/CC-MAIN-20150728002309-00129-ip-10-236-191-2.ec2.internal.warc.gz

CC-MAIN-2015-32

https://everything2.com/title/Dirichlet+Function

math

The Dirichlet function χ presents a particular problem for the theory of the Riemann integral. Consider this sequence of functions: f (t) = lim (cos (n! πt)) (1 if t = k/n! for k an integer and 0 otherwise), all of which are clearly Riemann integrable. This sequence of functions fn (t) converges to χ(t), where χ(t) = 0 when t is irrational and χ(t) = 1 when t is rational (the characteristic function of the rational numbers over the set of real numbers). This is not Riemann integrable because for any partition P you can make the Riemann sums equal either 0 or 1, by taking the points ci to be either rational or irrational. Thus, the space of all Riemann integrable functions is incomplete, since taking a Cauchy sequence will converge to χ, which is not Riemann integrable. This function motivated the theory of the Lebesgue integral, and is indeed Lebesgue integrable, with an integral (over any interval) of zero, because χ(t) is zero almost everywhere, i.e. zero everywhere except on a set of measure zero.

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CC-MAIN-2022-21

http://www.farhatyummy.com/drinks/homemade-refreshing-tamarind-juice/

math

4 ounces tamarind seeds with pulp, (seeds with pulp) 7 1/2 cups cold water, divided 3/4 to 1 cup sugar or more (depending on how tangy the tamarind is) A} Wash and rinse off the tamarind pulp. Put in a good size of a pot B} Put 2 cup of water and bring to a boil. Combine boiling water and tamarind pulp in a good size of a bowl. Now mash with a fork, let stand for 1 to 2 hours, then mash tamarind again. C} Press through a sieve into a bowl, pressing pulp firmly against the sieve to extract all liquid. Discard solids. D} Combine tamarind liquid and 1/2 cup water in a small saucepan over medium heat. E} Add sugar ring to a boil, stirring until sugar dissolves. F} Reduce heat, and simmer for about 3 to 5 minutes or until liquid thickens slightly. G} Remove from heat and a set aside to cool 5 minutes. H} Combine tamarind syrup with remaining 5 cups of water in a large pitcher I} Put in the fridge for few minutes to 1 hour K} Serve over ice

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CC-MAIN-2017-47

http://stochastix.wordpress.com/2012/07/03/vladimir-arnold-on-mathematical-models/

math

Vladimir Igorevich Arnold (1937-2010) on mathematical models : The scheme of construction of a mathematical theory is exactly the same as that in any other natural science. First we consider some objects and make some observations in special cases. Then we try and find the limits of application of our observations, look for counter-examples which would prevent unjustified extension of our observations onto a too wide range of events. As a result we formulate the empirical discovery that we made (for example, the Fermat conjecture or Poincaré conjecture) as clearly as possible. After this there comes the difficult period of checking as to how reliable are the conclusions. At this point a special technique has been developed in mathematics. This technique, when applied to the real world, is sometimes useful, but can sometimes also lead to self-deception. This technique is called modelling. When constructing a model, the following idealisation is made: certain facts which are only known with a certain degree of probability or with a certain degree of accuracy, are considered to be “absolutely” correct and are accepted as “axioms”. The sense of this “absoluteness” lies precisely in the fact that we allow ourselves to use these “facts” according to the rules of formal logic, in the process declaring as “theorems” all that we can derive from them. It is obvious that in any real-life activity it is impossible to wholly rely on such deductions. The reason is at least that the parameters of the studied phenomena are never known absolutely exactly and a small change in parameters (for example, the initial conditions of a process) can totally change the result. Say, for this reason a reliable long-term weather forecast is impossible and will remain impossible, no matter how much we develop computers and devices which record initial conditions. In exactly the same way a small change in axioms (of which we cannot be completely sure) is capable, generally speaking, of leading to completely different conclusions than those that are obtained from theorems which have been deduced from the accepted axioms. The longer and fancier is the chain of deductions (“proofs”), the less reliable is the final result. Complex models are rarely useful (unless for those writing their dissertations). The mathematical technique of modelling consists of ignoring this trouble and speaking about your deductive model in such a way as if it coincided with reality. The fact that this path, which is obviously incorrect from the point of view of natural science, often leads to useful results in physics is called “the inconceivable effectiveness of mathematics in natural sciences” (or “the Wigner principle”). Here we can add a remark by I.M. Gel’fand: there exists yet another phenomenon which is comparable in its inconceivability with the inconceivable effectiveness of mathematics in physics noted by Wigner – this is the equally inconceivable ineffectiveness of mathematics in biology. “The subtle poison of mathematical education” (in F. Klein‘s words) for a physicist consists precisely in that the absolutised model separates from the reality and is no longer compared with it. I did remove one comment in parentheses to shorten the passage. Hence, this is not an exact reproduction of the original passage in . The “Wigner Principle” that Arnold refers to is the thesis of Eugene Wigner’s famous article . Lastly, I do wonder how many theoretical chemists, theoretical physicists, and systems biologists out there were angered by Arnold’s “heretical” thoughts. Vladimir Igorevich Arnold, A.V. Goryunov (translator), On teaching mathematics, 1998. Eugene Paul Wigner, The Unreasonable Effectiveness of Mathematics in the Natural Sciences, February 1960.

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CC-MAIN-2013-48

https://web2.0calc.com/questions/help_54282

math

Please click on "Accept cookies" if you agree to the setting of cookies. Cookies that do not require consent remain unaffected by this, see 1. The scale factor is just the ratio between their two sides. So, for the first figure we have 3.5-6.5(I think), so that has a distance of 3. And, for the next figure, we have 7-13, which has a side length of 6. Thus, the scale factor is 6/3=2.

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CC-MAIN-2019-13

http://webapps.stackexchange.com/questions/tagged/conversion+weather

math

Web Applications Meta to customize your list. more stack exchange communities Start here for a quick overview of the site Detailed answers to any questions you might have Discuss the workings and policies of this site How to switch weather temperature from Fahrenheit to Celsius in Facebook events Facebook started showing the weather on event pages: How to switch temperature from Fahrenheit to Celsius? (or from Celsius to Fahrenheit) Apr 5 '13 at 10:13 newest conversion weather questions feed Please welcome jmac, Community Manager of the Rising Sun Hot Network Questions Can a person happen? Is "Zodanga happened" correct? Are there any English one-word equivalents for "je ne sais quoi"? XML format for game data How is Google Chrome managing authentication to sites? Teaching ukemi to children Color palette next to crop marks - function? How can a Seeker practice if the Snitch can't be touched prior to a Quidditch match? If studio monitors have flat response, what makes some better than others? What does Error 000885: Input Signature file does not have file extension indicate? Writing Roman numbers in Equation If the USS Equinox crew joined the USS Voyager, who would be captain? Which is faster: while(1) or while(2)? Is there a word or phrase meaning to plant my idea in someone else’s mind? How should I offer corrections on English for coworkers who are not native speakers? How is the poisson distribution a distribution? It seems more like a formula Which ball touches the ground first? What size gaps need to be kitten-proofed? Double integral proofs Hierarchical k-ary tree in C without relying on RAM Is there any theorem about figures of equal area and perimeter being congruent? what is the difference between "walking" and "go walking"? What's the difference between CraftSessionId and a normal PHP session? Why is polling accepted in web programming? Finding the largest of a series of numbers being XORed more hot questions Life / Arts Culture / Recreation TeX - LaTeX Unix & Linux Ask Different (Apple) Geographic Information Systems Science Fiction & Fantasy Seasoned Advice (cooking) Personal Finance & Money English Language & Usage Mi Yodeya (Judaism) Cross Validated (stats) Theoretical Computer Science Meta Stack Exchange Stack Overflow Careers site design / logo © 2014 stack exchange inc; user contributions licensed under cc by-sa 3.0

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CC-MAIN-2014-23

https://angelagreeneartandsole.com/qa/what-is-vertical-bar-used-for.html

math

- How do I insert a vertical bar in Word? - How do I insert a vertical line in Gmail signature? - Is a vertical line a function? - What is the vertical line symbol called? - What is a vertical line? - How do you use the vertical line test to identify a function? - How do you tell if a graph represents a function? - What is vertical bar on keyboard? - How do you type a vertical line? - How do I get a vertical bar on my keyboard? - What do two vertical lines mean in math? - What does vertical line test mean? - What does a vertical line mean on a graph? - Is a vertical line a linear equation? How do I insert a vertical bar in Word? Use a Bar Tab to Add a Vertical LineSelect the paragraph where you want to add the vertical line.Go to Ribbon > Home. Click the Tabs button at the bottom of the dialog.In the Tab stop position box, enter the position where you want the vertical line to appear. Click the Bar button in the Alignment section.. How do I insert a vertical line in Gmail signature? Scroll down until you see the ‘Signature’ box. Type in your name and title separated by a vertical line. The vertical line key is above the ‘enter/return’ key on your keyboard and is the same key as the forward slash “\”. Is a vertical line a function? For a relation to be a function, use the Vertical Line Test: Draw a vertical line anywhere on the graph, and if it never hits the graph more than once, it is a function. If your vertical line hits twice or more, it’s not a function. What is the vertical line symbol called? The vertical line, also called the vertical slash or upright slash ( | ), is used in mathematical notation in place of the expression “such that” or “it is true that.” This symbol is commonly encountered in statements involving logic and sets. Also see Mathematical Symbols. What is a vertical line? : a line perpendicular to a surface or to another line considered as a base: such as. a : a line perpendicular to the horizon. b : a line parallel to the sides of a page or sheet as distinguished from a horizontal line. How do you use the vertical line test to identify a function? To use the vertical line test, take a ruler or other straight edge and draw a line parallel to the y-axis for any chosen value of x. If the vertical line you drew intersects the graph more than once for any value of x then the graph is not the graph of a function. How do you tell if a graph represents a function? Use the vertical line test to determine whether or not a graph represents a function. If a vertical line is moved across the graph and, at any time, touches the graph at only one point, then the graph is a function. If the vertical line touches the graph at more than one point, then the graph is not a function. What is vertical bar on keyboard? Alternatively referred to as a vertical bar, the pipe is a computer keyboard key “|” is a vertical line, sometimes depicted with a gap. This symbol is found on the same United States QWERTY keyboard key as the backslash key. … Keyboard help and support. How do you type a vertical line? You can type a straight vertical line, or “|,” on most modern keyboards dating back to some of the 1980s IBM PCs. It’s generally found above the backslash, so you can type a “|” by holding down the shift key and hitting the “” key. How do I get a vertical bar on my keyboard? google said,Shift-\ (“backslash”).German keyboard it is on the left together with < and > and the Alt Gr modifier key must be pressed to get the pipe.Note that depending on the font used, this vertical bar can be displayed as a consecutive line or by a line with a small gap in the middle.More items… What do two vertical lines mean in math? Every number on the number line also has an absolute value, which simply means how far that number is from zero. The symbol for absolute value is two vertical lines. … For example, the absolute value of “negative 10” is ten, and the absolute value of “positive 10” is also 10. What does vertical line test mean? The vertical line test is a graphical method of determining whether a curve in the plane represents the graph of a function by visually examining the number of intersections of the curve with vertical lines. What does a vertical line mean on a graph? A vertical line is one the goes straight up and down, parallel to the y-axis of the coordinate plane. All points on the line will have the same x-coordinate. … A vertical line has no slope. Or put another way, for a vertical line the slope is undefined. Is a vertical line a linear equation? Besides horizontal lines, vertical lines are also special case of linear equations. Similar to the lesson for the horizontal lines case, we will practice on determining the equations for graph where all the x points have the same value.

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CC-MAIN-2021-04

http://notesforfree.com/2017/12/17/jee-mains-2016-solutions/

math

JEE (MAINS) 2016 with Solutions An observer looks at a distant tree of height 10 m with a telescope of magnifying power of 20. To the observer the tree appears : (1) 20 times nearer (2) 10 times taller (3) 10 times nearer (4) 20 times taller Arrange the following electromagnetic radiations per quantum in the order of increasing energy :- A : Blue light B : Yellow light C : X–ray D : Radiowave (1) B, A, D, C (2) D, B, A, C (3) A, B, D, C (4) C, A, B, D Which one of the following ores is best concentrated by froth floatation method ? (1) Magnetite (2) Siderite (3) Galena (4) Malachite Which one of the following statements about water is FALSE ? (1) Water is oxidized to oxygen during photosynthesis. (2) Water can act both as an acid and as a base. (3) There is extensive intramolecular hydrogen bonding in the condensed phase. (4) Ice formed by heavy water sinks in normal water The concentration of fluoride, lead, nitrate and iron in a water sample from an underground lake was found to be 1000 ppb, 40 ppb, 100 ppm and 0.2 ppm, respectively. This water is unsuitable for drinking due to high concentration of : (1) Fluoride (2) Lead (3) Nitrate (4) Iron The distillation technique most suited for separating glycerol from spentlye in the soap industry is : (1) Simple distillation (2) Fractional distillation (3) Steam distillation (4) Distillation under reduced pressure

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https://www.shaalaa.com/question-bank-solutions/solve-given-inequality-show-graph-solution-number-line-3x-2-2x-1-algebraic-solutions-linear-inequalities-one-variable-their-graphical-representation_13498

math

Solve the given inequality and show the graph of the solution on number line: 3x – 2 < 2x +1 3x – 2 < 2x +1 ⇒ 3x – 2x < 1 + 2 ⇒ x < 3 The graphical representation of the solutions of the given inequality is as follows. Concept: Algebraic Solutions of Linear Inequalities in One Variable and Their Graphical Representation Is there an error in this question or solution?

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CC-MAIN-2021-10

http://scessayvudz.tycoa.us/solution-to-math-problems.html

math

Wed, 30 may 2018 16:26:00 gmt solution math problems pdf - a collection of problems in di erential calculus problems given at the math 151 solution to the. Find practice math problems with answers in algebra & calculus from the cymath online math solver the cymath equation solver makes solving math problems easy. Solve calculus and algebra problems online with cymath math problem solver with steps to show your work get the cymath math solving app on your smartphone. Beginning differential calculus : problems on the limit of a function as x approaches a fixed constant uc davis / [email protected] And herein lies the beauty of math: you can use pemdas to your heart’s content that’s how my brain understands the order of operations, too. A solution to each of these problems carries a $1 million reward, only one of which open problem garden, a wiki of open problems in mathematics planet math. I can't solve hard math problems i always give up and look at the solution what should i do to fix that. Up close: statistics a snapshot of mathematics problems and implications math disabilities, like other learning disorders, have the power to keep children from. Unsolved problems in mathematics the unsolved problems in math which should challenge the general population they say there is no solution to this kind of. Rutgers sample calc 1 exam problems with answers math uc merced old calculus exams with solutions, math 21 mixed collections of mathematics exams with solutions. Advanced mathematics textbook solutions and answers from chegg get help 22,000 isbns in math solve advanced mathematics textbook problems and be. Sometimes gmat students, especially folks who are not very confident in math, think about gmat math problems in a very binary framework — they get the problem.Alcohol problems and solutions: debunking myths and sharing effective peer-reviewed ways to reduce drinking problems & live healthier, for nearly 20 years. Sample problems are under the links in the sample problems column and the corresponding review material is under the concepts column new problems. Chemistry problems: learn how to solve chemistry problems. Dilution problems #1 - 10 if you dilute 175 ml of a 16 m solution of licl there is no standard way to write the subscripts in problems of this type. Multiple solutions to problems in mathematics teaching: do teachers really value problems so that they learn to value different solution strategies in the process. Math tutoring in tampa, fl mathbusters provides one-on-one math tutoring, science tutoring, and english tutoring services in tampa, fl we also offer group tutoring. Word problems made simple is a must have app for those students/learners who wish to develop the thinking required to solve math word problems the topics. Is there any way to get a printable version of the solution calculus i (practice problems go to the download page for the site . Assorted math puzzles and quizzes not all puzzles have a solution here but if you need help you can ask at the math is fun forum puzzles index. Is there any way to get a printable version of the solution to a problems for the integration techniques tutorialmathlamaredu/download. Webmath is designed to help you solve your math problems composed of forms to fill-in and then returns analysis of a problem and, when possible, provides a step-by. 12 responses to gmat solution and mixing problems fully solving the problem can boost your mental math skills and allow you to check your answers to data. Solving equations this sections x - 4 = 10 solution 2x - 4 = 10 solution 5x - 6 = 3x - 8 solution solution solution 2(3x math medics, llc. These math worksheets each have a number of simple division word problems after reading the math word problem and understanding the 'real world scenario', the. Math 105- calculus for economics & business sections 103 & 104 : optimization problems how to solve an optimization problem 1 solution. 1001 solved problems in engineering mathematics jaime r tiong romeo a rojas, jr. Solving math problems can intimidate sixth-graders, but by using a few simple formulas, students can easily calculate answers to worksheet questions.Download 2018. Education database.

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CC-MAIN-2018-39

https://awm-math.org/abstract/equivariant-global-hopf-bifurcation-in-abstract-nonlinear-parabolic-equations/

math

We propose a method for studying symmetric global Hopf bifurcation problems in a parabolic system. The objective is to detect unbounded branches of non-constant periodic solutions that arise from an equilibrium point and describe their symmetric properties in detail. The method is based on the twisted equivariant degree theory, which counts orbits of solutions to symmetric equations, similar to the usual Brouwer degree, but on the report of their symmetric properties. Equivariant Global Hopf Bifurcation in Abstract Nonlinear Parabolic Equations Arnaja Mitra, The University of Texas at DallasAuthors: Zalman Balanov, Wieslaw Krawcewicz, Arnaja Mitra, Dmitrii Rachinskii 2023 AWM Research Symposium

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CC-MAIN-2024-10

http://mathforum.org/library/drmath/view/52023.html

math

Integral of e^(e^x) Date: 12 May 1995 10:55:54 -0400 From: Andrew Ricker What is the integral of e to e to the x power? Date: 16 May 1995 22:21:01 -0400 From: Dr. Sydney Dear Andrew, Good question! When you say what is the integral of e to the e to the x power, do you mean e^(e^x) or (e^e)^x? I assume you mean the former because the latter would follow the same pattern of what happens when you integrate any constant raised to the x power (If you are unclear on how to do this, feel free to write back!). So, let's think about integrating e^(e^x). Hmmm..... Well, it seems to defy all of the standard tricks and tools of integration like substitution, trig substitution, parts, etc... I couldn't find it in a table of integrals (though I must admit I was skimming through). So, how could we approach this? It seems to me that within limits, you could approximate this integral with a Taylor expansion. Do you know what Taylor polynomials are? If not, write back and we'll explain. You could express e^(e^x) as a Taylor polynomial and then integrate that polynomial (Polynomials are certainly much easier to integrate!). If you are looking for a nice, pat answer, I don't think there is one. But, you could give these polynomials a try... If you have any other questions, or if you want to know more about what I have said, feel free to write back. Thanks for the question! --Sydney, "Dr. Math" Search the Dr. Math Library: Ask Dr. MathTM © 1994- The Math Forum at NCTM. All rights reserved.

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CC-MAIN-2018-17

https://repub.eur.nl/pub/18217

math

A new approximation algorithm for the multilevel facility location problem Discrete Applied Mathematics , Volume 158 - Issue 5 p. 453- 460 In this paper we propose a new integer programming formulation for the multilevel facility location problem and a novel 3-approximation algorithm based on LP-rounding. The linear program that we use has a polynomial number of variables and constraints, thus being more efficient than the one commonly used in the approximation algorithms for these types of problems. |Econometric Institute Reprint Series| |Discrete Applied Mathematics| |Organisation||Erasmus Research Institute of Management| Gabor, A.F, & van Ommeren, J.C.W. (2010). A new approximation algorithm for the multilevel facility location problem. Discrete Applied Mathematics, 158(5), 453–460. doi:10.1016/j.dam.2009.11.007

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CC-MAIN-2023-23

https://academia.stackexchange.com/questions/180563/associate-professors-without-a-phd?noredirect=1

math

The title "Associate Professor", which is commonly used in North America, is "usually connected to tenure" in that it is almost exclusively given to tenured or permanent professors who are higher in rank than Assistant Professors. This has also been explained in previous Academia.SE questions, for example: Within the last year, someone also asked here about the awarding of the Associate Professor title to people without doctorates: Is it true, that there are associate professors, full professors and University provosts without a doctorate in the Western Continental Europe?, and we learned there that in UK there are Professorships awarded in Law and Engineering (and I wouldn't be surprised if also in Medicine) to people without doctorates. I wonder if there's any precedent for people being given this title without a PhD in Canada? I wouldn't be surprised if people have this title after getting a JD, MD, PharmD, PEng, etc., so even more specifically I am wondering about people who have only an undergrad degree and/or Masters. The reason for my question, is because it looks like a U15 university in Canada (I might as well just say openly that it's University of Waterloo) says that they will be re-labeling Continuing Lecturers into Associate Professors: Continuing Lecturers (soon to become Associate Professors), often enough do not have a PhD (for example here and here). I understand that other Canadian universities (e.g. University of Toronto and McMaster University) also have the "teaching-stream Professor" positions, but advertisements for applying to those positions suggest that a PhD is required. Since Charles Grant astutely pointed out that Freeman Dyson's full professorship at Cornell was without a PhD, I'd like to be clear that I'm not looking for "one-time exceptional cases" that lasted only 1 year and went to someone who helped Feynman get the Nobel Prize, but more for "regular" positions that are offered frequently (e.g. there's at least one job advertisement at the university per year for a job with the "Associate Professor" title).

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CC-MAIN-2024-18

https://mahustlerszone.wordpress.com/category/fashion/page/2/

math

#1 The Ratchet Eye This transcends ratchet with it’s amazing creativity! #2 The Ratchet Rainbow Looks kinda like a cartoon superhero? #3 Strawberry Blonde Looks pretty crazy, but I think it’s just extensions #4 Sparkle Princess Okay, at least you gotta respect the time and effort that must’ve gone into this. #5 Hot Mess Does this weave come with super powers? Dolla Dolla Bills Y’all! #7 Hair By Skittles Well, if she has little kids I bet they like it. Is that a patch? #9 Cottn Candy? Wonder what it looks like down? Wonder if it comes down at all? #10 The Tribal Bun Looks pretty good from the front, though? #11 Mr. Ratchet This actually looks really difficult and complicated. #12 The Super Sayyan Wonder if she transforms? #13 The Crazy Hat Think she went hunting that day? #14 The Jolly Ranchers LMFAOOOOO….IM DONE!! XD

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CC-MAIN-2022-33

https://jobs.three.co.uk/location/bromley-jobs/5965/2635167-6269131-2648110-3333135-2654588/4

math

Customer Jobs ( 8 ) Digital Jobs ( 1 ) Finance Jobs ( 10 ) Human Resources Jobs ( 5 ) Legal & Regulatory Jobs ( 7 ) Marketing Jobs ( 4 ) Marketing, Customer and Digital Products & Big Data Jobs ( 1 ) Retail Customer Advisor Jobs ( 120 ) Retail Store Management Jobs ( 16 ) The People Team (HR & Facilities) Jobs ( 1 ) Please try a different keyword/location combination or broaden your search criteria. Not found the job you were looking for? View all jobs

s3://commoncrawl/crawl-data/CC-MAIN-2018-39/segments/1537267157203.39/warc/CC-MAIN-20180921131727-20180921152127-00097.warc.gz

CC-MAIN-2018-39

https://greed-head.com/how-to-find-an-eigenvector/

math

How to find an eigenvector? Step 1: Determine the eigenvalues of the given matrix A using the equation det (A – λI) = 0, where I is equivalent order… How to find eigenvalues and eigenvectors? Characteristic Polynomial. That is, start with the matrix and modify it by subtracting the same variable from each… How to find the eigenvalues of a matrix? Step 1: Make sure the given matrix A is a square matrix. Also, determine the identity matrix I of the same order. How do you calculate matrix? Multiply the entry in the first row and second column by the entry in the second row and first column. If we are finding the determinant of the 2×2 matrix A, then calculate a12 x a21. 3. Subtract the second value from the first value 2×2 Matrix. 2×2 Matrix Determinant Formula. Can an eigenvector be a zero vector? Eigenvalues may be equal to zero. We do not consider the zero vector to be an eigenvector: since A 0 = 0 = λ 0 for every scalar λ, the associated eigenvalue would be undefined. If someone hands you a matrix A and a vector v, it is easy to check if v is an eigenvector of A: simply multiply v by A and see if Av is a scalar multiple of v. What is an eigenvector of a covariance matrix? Eigen Decomposition of the Covariance Matrix Eigen Decomposition is one connection between a linear transformation and the covariance matrix. An eigenvector is a vector whose direction remains unchanged when a linear transformation is applied to it. It can be expressed as

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CC-MAIN-2022-21

https://idealha.ir/profiting-from-the-english-premier-league/

math

A related point is that Kelly assumes the only important thing is long-term wealth. Most people also care about about the path to get there. Two people dying with the same amount of money need not have had equally happy lives. Kelly betting leads to highly volatile short-term outcomes which many people find unpleasant, even if they believe they will do well in the end. More recently, the strategy has seen a renaissance, in response to claims that legendary investors Warren Buffet and Bill Gross use a variant of the Kelly criterion. The formula is used to determine the optimal amount of money to put into a single trade or bet. Kelly began to develop investing strategies according to probability theory. These theories also applied to gambling strategies, too, and these investing strategies are part of what is now called game theory. Here you bet the full “single bet Kelly” percentage of 1,4% on every bet. While most calculators compute the Kelly Criterion in terms of odds and edges , this calculator is designed to sneak a peek here work in terms of current and future prices . Please check your local laws or consult with legal counsel before attempting to play poker online. This paper defines an equivalent stake for performance index bets, and from this are derived several measures of over-round for a performance index. Top Recommended Arbitrage Betting Software: If you wager one buck at a time, you win almost certainly. First, they require punters to be able to accurately assess the probability of something happening and compare this number to the odds they are getting. If you are tossing a coin, this is easy, because you are dealing with the mathematical certainty that heads will come up, in the long run, 50% of the time. If you are then offered odds of $3.50, which imply heads will only come up 29% of the time, it is relatively simple to work out how “wrong” the odds are and bet accordingly. Juxtaposed against inebriated party-goers, Bill and a small group of newfound nerdy friends sat assiduously at the blackjack tables and discussed probability theory between rounds. Using Hash Ai To Simulate Company Survival Rates Results obtained for the Triple Kelly portfolio confirm that over-investment can have disastrous outcomes, with a maximum drawdown very close to 95%. Recently, few researchers are starting to study how the Kelly criterion can be used on option portfolios. Aurell et al. are the first to use the Kelly criterion in order to specify a model to price and hedge derivatives in incomplete markets. Wu and Chung implement an algorithm that seems able to find the most profitable option portfolio using the Kelly criterion. Using data from the Taiwan Stock Exchange Index they demonstrate that trading signals obtained from traditional strategies were not necessary when using the Kelly criterion. Finally, Wu and Hung use the Kelly criterion within a framework where a strategy involving trading on options exercised on the simple index futures is defined. We need you, and we want you to be able to keep improving your strategies so you win more. However, the bettor has assessed the true odds of Hawthorn winning the Grand Final to be $1.90 which is implying a percentage chance of victory at 52.63%. In essence, the Kelly Criterion calculates the proportion of your own funds to bet on an outcome whose odds are higher than expected. Kelly Vs Optimal Video Poker Strategy 1) for a 2X bet you should not bet anything unless the probability of winning is above 50%. In fact, if the probability is below 50%, you should try to find a way to take the other side of the bet or trade . In this example you have a 60% probability of doubling your money; the Kelly Criterion says that you should bet 20% of your bankroll . The Kelly Criterion is based on solid mathematics and informative post has a lot to recommend it. For those adept at calculating true probabilities, it offers a dynamic way of maximising their rewards. It is important to remember, however, that the Kelly Criterion is essentially a staking system. It will not identify potential bets and is not an automatic route to profit. It should therefore be used with caution, particularly by those new to betting. Even though the formula says that one should bet 98% of your bankroll when you have a 99% chance of winning a 2X bet, that still leaves you with a 1% chance of going broke—too high for me, at this stage in my life. For sports betting, there is the added complication that the true odds on an outcome are not known. When calculating your Kelly bet, your estimate may well differ significantly from the true odds.

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https://blog.collegefindme.com/math/

math

Mateo Dordi ‘23, University of California Berkeley I major in Applied Mathematics at UC Berkeley. It’s the application of mathematical methods by different fields such as science, engineering, business, computer science, and industry. I’ve always enjoyed doing math and it was something that came naturally to me so I decided to make it my major. I am currently taking Math 53 here at Berkeley which is Multi Variable Calculus. In high school, I took AP Calculus AB/BC in the 11th grade which really peaked my interest for math. I enjoyed working through each problem and really understanding the fundamentals and basics behind each and every problem in math. It showed me the simplicity and beauty behind mathematics and its implications in our day to day life. Though I didn’t really complete any projects, I did work on proving a theorem in Calculus class which was really fun, even though it took my friend and I almost a week to complete it. The department is a little smaller than the big name majors, but there are still a plethora of facilities and research opportunities for math majors to pursue. There aren’t too many applied math majors I know here but a lot of people I know are taking the same level math class as I am. The few people that are majoring in math really love the faculty. They’re very helpful since it’s a smaller program compared to something like Computer Science. Math is in every single thing that you do. It teaches you valuable lessons and if you can get a math degree, you can pretty much do anything. I hope to eventually get into software and use the math knowledge I have to advance the company I am working at. Some other fields that math majors can get into include being Statisticians, Mathematicians, Math Professors, and basically anything Economics or Finance related.

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https://www.brooklandjm.herts.sch.uk/maths-237/

math

Problem solving relates to using a wide range of mathematical skills. Problems may involve your use of shape and space, addition and subtraction, multiplication and division- any area of maths in fact. However, reasoning skills will need to be used such as logical thinking, working systematically (doing things in a particular order) and reading comprehension skills. Try and follow the steps below to help you solve the problems given. 1) As with any maths problem you ALWAYS need to carefully READ what the problem is asking/ telling you. Read it aloud if you can. 2) UNDERSTAND which area of maths the problem is related to and which OPERATIONS you may need to use (if any). - First I will need to... Then I will... 3) Realise what you ALREADY KNOW about the problem (the problem itself will often give you all the information you need to solve it). - I know that... so I also know that... 4) CONTINUE solving the problem- BREAK IT DOWN into smaller steps if you need to. Build it/ draw it/ say it 5) CHECK your solution- work backwards using inverse operations (if appropriate).

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https://par.nsf.gov/biblio/10288371-minimizers-cahn-hilliard-energy-functional-under-strong-anchoring-conditions

math

In materials that undergo martensitic phase transformation, macroscopic loading often leads to the creation and/or rearrangement of elastic domains. This paper considers an example involving a single-crystal slab made from two martensite variants. When the slab is made to bend, the two variants form a characteristic microstructure that we like to call “twinning with variable volume fraction.” Two 1996 papers by Chopra et al. explored this example using bars made from InTl, providing considerable detail about the microstructures they observed. Here we offer an energy-minimization-based model that is motivated by their account. It uses geometrically linear elasticity, and treats the phase boundaries as sharp interfaces. For simplicity, rather than model the experimental forces and boundary conditions exactly, we consider certain Dirichlet or Neumann boundary conditions whose effect is to require bending. This leads to certain nonlinear (and nonconvex) variational problems that represent the minimization of elastic plus surface energy (and the work done by the load, in the case of a Neumann boundary condition). Our results identify how the minimum value of each variational problem scales with respect to the surface energy density. The results are established by proving upper and lower bounds that scale the same way. Themore » Minimizers for the Cahn--Hilliard energy functional under strong anchoring conditions We study analytically and numerically the minimizers for the Cahn-Hilliard energy functional with a symmetric quartic double-well potential and under a strong anchoring condition(i.e., the Dirichlet condition) on the boundary of an underlying bounded domain. We show a bifurcation phenomenon determined by the boundary value and a parameter that describes the thickness of a transition layer separating two phases of an underlying system of binary mixtures. For the case that the boundary value is exactly the average of the two pure phases, if the bifurcation parameter is larger than or equal to a critical value, then the minimizer is unique and is exactly the homogeneous state. Otherwise, there are exactly two symmetric minimizers. The critical bifurcation value is inversely proportional to the first eigenvalue of the negative Laplace operator with the zero Dirichlet boundary condition. For a boundary value that is larger (or smaller) than that of the average of the two pure phases, the symmetry is broken and there is only one minimizer. We also obtain the bounds and morphological properties of the minimizers under additional assumptions on the domain.Our analysis utilizes the notion of the Nehari manifold and connects it to the eigenvalue problem for the negative Laplacian more » - Award ID(s): - Publication Date: - NSF-PAR ID: - Journal Name: - SIAM journal on applied mathematics - Page Range or eLocation-ID: - Sponsoring Org: - National Science Foundation More Like this Variational boundary conditions based on the Nitsche method for fitted and unfitted isogeometric discretizations of the mechanically coupled Cahn-Hilliard equation.The primal variational formulation of the fourth-order Cahn-Hilliard equation requires C1-continuous finite element discretizations, e.g., in the context of isogeometric analysis. In this paper, we explore the variational imposition of essential boundary conditions that arise from the thermodynamic derivation of the Cahn-Hilliard equation in primal variables. Our formulation is based on the symmetric variant of Nitsche's method, does not introduce additional degrees of freedom and is shown to be variationally consistent. In contrast to strong enforcement, the new boundary condition formulation can be naturally applied to any mapped isogeometric parametrization of any polynomial degree. In addition, it preserves full accuracy, including higher-order rates of convergence, which we illustrate for boundary-fitted discretizations of several benchmark tests in one, two and three dimensions. Unfitted Cartesian B-spline meshes constitute an effective alternative to boundary-fitted isogeometric parametrizations for constructing C1-continuous discretizations, in particular for complex geometries. We combine our variational boundary condition formulation with unfitted Cartesian B-spline meshes and the finite cell method to simulate chemical phase segregation in a composite electrode. This example, involving coupling of chemical fields with mechanical stresses on complex domains and coupling of different materials across complex interfaces, demonstrates the flexibility of variational boundary conditions in the context ofmore » Inverting the variable fractional order in a variable-order space-fractional diffusion equation with variable diffusivity: analysis and simulationAbstract Variable-order space-fractional diffusion equations provide very competitive modeling capabilities of challenging phenomena, including anomalously superdiffusive transport of solutes in heterogeneous porous media, long-range spatial interactions and other applications, as well as eliminating the nonphysical boundary layers of the solutions to their constant-order analogues.In this paper, we prove the uniqueness of determining the variable fractional order of the homogeneous Dirichlet boundary-value problem of the one-sided linear variable-order space-fractional diffusion equation with some observed values of the unknown solutions near the boundary of the spatial domain.We base on the analysis to develop a spectral-Galerkin Levenberg–Marquardt method and a finite difference Levenberg–Marquardt method to numerically invert the variable order.We carry out numerical experiments to investigate the numerical performance of these methods. In this work we present a systematic review of novel and interesting behaviour we have observed in a simplified model of a MEMS oscillator. The model is third order and nonlinear, and we expressit as a single ODE for a displacement variable. We find that a single oscillator exhibits limitcycles whose amplitude is well approximated by perturbation methods. Two coupled identicaloscillators have in-phase and out-of-phase modes as well as more complicated motions.Bothof the simple modes are stable in some regions of the parameter space while the bifurcationstructure is quite complex in other regions. This structure is symmetric; the symmetry is brokenby the introduction of detuning between the two oscillators. Numerical integration of the fullsystem is used to check all bifurcation computations. Each individual oscillator is based on a MEMS structure which moves within a laser-driven interference pattern. As the structure vibrates, it changes the interference gap, causing the quantity of absorbed light to change, producing a feedback loop between the motion and the absorbed light and resulting in a limit cycle oscillation. A simplified model of this MEMS oscillator, omitting parametric feedback and structural damping, is investigated using Lindstedt's perturbation method. Conditions are derived on the parameters of the modelmore » Abstract We prove a regularity theorem for the free boundary of minimizers of the two-phase Bernoulli problem, completing the analysis started by Alt, Caffarelli and Friedman in the 80s. As a consequence, we also show regularity of minimizers of the multiphase spectral optimization problem for the principal eigenvalue of the Dirichlet Laplacian.

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https://www.britannica.com/story/will-we-ever-run-out-of-sudoku-puzzles

math

Realistically, no! There are 6,670,903,752,021,072,936,960 possible solvable Sudoku grids that yield a unique result (that’s 6 sextillion, 670 quintillion, 903 quadrillion, 752 trillion, 21 billion, 72 million, 936 thousand, 960 in case you were wondering). That's way more than the number of stars in the universe. Think of it this way: if each of the approximately 7.3 billion people on Earth solved one Sudoku puzzle every second, they wouldn’t get through all of them until about the year 30,992. But surely not every possible grid layout is all that different from every other one, right? That number is so inconceivably huge – and seemingly random – that within those seven commas there’s got to be at least a few similar or even near duplicate puzzles. So how many are truly distinct? Combinatorics is a field of math concerned with problems of selection, arrangement, and operation within a finite or discrete system. A Latin square is an n-by-n grid filled with n distinct symbols in such a way that each symbol appears only once in each row and column. A solved Sudoku grid is a Latin Square of order nine, meaning n=9. So it is a finite system on which combinatorics can be applied. Using combinatorics, we can take any one Sudoku grid and, with various simple tricks, create enough unique grids for you to do one each day for the next century. Simply by transposing and rotating the grid or interchanging columns and rows we get exponentially more unique puzzles. But all of the puzzles created this way are essentially the same; the difficulty and probable starting points won’t vary drastically. Of all the unique possibilities for a Sudoku puzzle only a (theoretically) more manageable 5,472,730,538 are essentially different and can't be somehow derived from each other. That would still take a single person more than 173 years to get through even if he or she could finish one every second. So no need to pace yourself.

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https://apps.dtic.mil/sti/citations/AD0759714

math

Notes on a Problem Involving Permutations as Subsequences STANFORD UNIV CA DEPT OF COMPUTER SCIENCE Pagination or Media Count: The problem attributed to R. M. Karp by Knuth is to describe the sequences of minimum length which contain, as subsequences, all the permutations of an alphabet of n symbols. The paper catalogs come of the easy observations on the problem and proves that the minimum lengths for n5, n6 and n7 are 19, 28 and 39 respectively. Also presented is a construction which yields for n2 many appropriate sequences of length n sup 2-2n4 so giving an upper bound on length of minimum strings which matches exactly all known values. - Theoretical Mathematics

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https://reference.wolfram.com/language/ref/PolygonalNumber.html

math

gives the n triangular number . gives the n r-gonal number . - Mathematical function, suitable for both symbolic and numerical manipulation. - PolygonalNumber[n] is generically defined as . - PolygonalNumber[r,n] is generically defined as . - PolygonalNumber[r,n] can be interpreted as the number of points arranged in the form of n-1 polygons of r sides. For instance for r=3 and n=4: - PolygonalNumber automatically threads over lists. Examplesopen allclose all Basic Examples (2) Properties & Relations (9) Introduced in 2016

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https://forum.jimmyjoy.com/t/low-calories-idea/1803?page=3

math

If you want to loose weight a high-protein powder would be good. You could combine the Active version with some protein powder. One scoop would give you as many calories as the conventional shake, but you could add more water per scoop and still get a good satiety. Let’s say your metabolism is 1700 kcal (which is really low for your weight) Add 300 kcal per day (which is extremely low) It gives 2000 Add 4 intense workout per week : 500 kcal * 4 / 7 = +285 2000+285 = 2285 kcal for maintenance How can you gain weight with 2100? That depends on your height and activity level. There are several calculators to be found on the internet. If you really want to know you should use several ones and take the arithmetic mean of the recommended numbers. If you do not reach your weight goals after some time, you should reevaluate. According to the calculator that I use you would lose weight at 2100kcal with your activity level: I have used the same calculator and I lost 10kg in 2020 while keeping a large part of my strength/muscle.

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https://www.physicsforums.com/threads/physics-bernoullis-equation.417198/

math

A horizontal water main with a cross-sectional area of 184 cm2 necks down to a pipe of area 45.0 cm2. Meters mounted in the flow on each side of the transition coupling show a change in gauge pressure of 70.0 kPa. Determine the flow rate through the system, taking the fluid to be ideal. The Attempt at a Solution I'm confused about how to do this problem without any velocity given. Thank-you!!

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https://www.thenakedscientists.com/forum/index.php?topic=52696.0

math

0 Members and 1 Guest are viewing this topic. But why are so many diagrams incorrect? Have I still misunderstood your explanation? Thanks for your explanation. I've always understood that the electric sine wave and the magnetic sine wave, though peaking at the same time, vibrate in different planes. One is in the XY plane and the other in the XZ plane. There are any number of diagrams published showing this. Hence my question.If I've understood your reply correctly, both vibrate in the XY plane, either side of the direction of travel along the X axis. This certainly explains polarisation.But why are so many diagrams incorrect? Have I still misunderstood your explanation? which of its orthogonal electric and magnetic components is eliminated? [near] the lines of magnetic force produced by magnets ... the plane of polarization is caused to rotate.

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https://thrificapeb.web.app/770.html

math

It develops mathematical thinking and reasoning skills that are essential for further learning of mathematics. Calicut university entrance exam syllabus 2020 pdf. Faculty members and students are requested to download the below syllabus and prepare accordingly for the examination and schedule. Seymour lipschutz, linear algebra, mcgraw hill book company, 2001. Mathematics is of everincreasing importance to our society and everyday life. Ma8151 syllabus engineering mathematics 1 regulation 2017 anna university free download. Furthermore, we have arranged all the details on this single page related to the tezpur university syllabus 2020. Calicut university entrance exam 2020 is conducted to provide admission for qualified students. Brown university mathematics department course syllabi version 0. Pdf anna university syllabus for regulations 2017 r2017. Prerequisites ma 52, 54, or permission of the instructor. An introduction to differential and riemannian geometry, oxford university press. All students should be aware that the department of mathematical sciences takes the university code on academic integrity at njit very seriously and enforces it strictly. Applied mathematics syllabus this syllabus will contribute to the development of the ideal caribbean person as articulated by the caricom heads of government in the following areas. Ma8151 syllabus engineering mathematics 1 the goal of this course is to achieve conceptual understanding and to retain the best traditions of. H2 mathematics is designed to prepare students for a range of university courses, such as mathematics, science, engineering and related courses, where a good foundation in mathematics is required. Ma8251 syllabus engineering mathematics 2 regulation 2017. Ma8151 engineering mathematics i syllabus notes question. Courses in mathematics, 2010 mathematics honours paperwise distribution. Lewis, phd, gordon mckay professor of computer science, harvard university deborah abel. Today, mathematics is essential in virtually all fields of human endeavor, including business, the. These syllabus documents will also be available in the official website of the alagappa university. Department of mathematics university of toronto apm346s differential equations 2017. University mathematics bi spring 2020 coordinated course syllabus njit academic integrity code. Mathematics course is an amalgamation of indepth knowledge of geometry, trigonometry, calculus and other theories. Download grade 10 12 mathematics zambian syllabus pdf document on this page you can read or download grade 10 12 mathematics zambian syllabus pdf in pdf format. A solid understanding of linear algebra and a liking for abstract mathematics. Mathematics syllabus rationale the guiding principles of the mathematics syllabus direct that mathematics as taught in caribbean schools should be relevant to the existing and anticipated needs of caribbean society, related to the abilities and interests of caribbean students and aligned with the philosophy of the educational system. Engineering mathematics 1 syllabus ma8151 pdf download free. Alagappa university courses and syllabus download here. Here is the syllabus for all courses offered by the university. These include the board of studies k10 curriculum framework and statement of equity principles and the melbourne declaration on educational goals for young australians december 2008. Here are the files provided, you can just download the pdf files by the links available by clicking on it. Undergraduate syllabus mathematics university of calcutta. Mathematics syllabus, course structure, subjects, books. Check out engineering mathematics 1styear pdf notes download. Pdf ma8251 engineering mathematics ii lecture notes. The mathematics curriculum comprises a set of syllabuses spanning 12 years, from primary to pre university, and is compulsory up to the end of secondary education. Download link is provided and students can download the anna university ma8251 engineering mathematics ii emii syllabus question bank lecture notes part a 2 marks with answers part b marks and part c 15 marks question bank with an answer, all the materials are listed below for the students to make use of it and score good maximum marks with our study materials. We also provided the calicut university entrance exam syllabus 2020 in pdf format. Representation of functions limit of a function continuity derivatives differentiation rules. Applied mathematics syllabus makes provision for this diversity through two carefully articulated units that are available to students. We have provided mathematics 1st year study materials and lecture notes for cse, ece, eee, it, mech, civil, ane, ae, pce, and all other branches. Engineering mathematics 1styear pdf notes download. Candidates who want to prepare for the exams must first know the syllabus. To view syllabi prior to fall 2016, go to exhibits. Contents introduction 1 math 42 introduction to number theory 2. Regulations the following regulations will be observed by m. Get an adequate knowledge about the topics to cover from the csir net syllabus mathematics pdf so that you. The total duration of the course is two years hereafter, course refers to the m. It also explores related topics like computer science and statistics. On this page you can read or download zimsec o level mathematics syllabus 2018 in pdf format. A course on group theory, oxford university press, 2004. Instructors should use these templates whichever is appropriate to generate syllabi for. Mathematics northeastern university college of science. Ma6151 engineering mathematics 1 anna university regulation 20 syllabus syllabus regulation. To view syllabi, select an academic term, then browse courses by subject. Ma8151 engineering mathematics i anna university common to all department first semester regulation 2017 syllabus. Introduction to limits and derivatives as preparation for further courses in calculus. Brown university mathematics department course syllabi. This degree course helps students in building a good foundation base for pursuing higher studies. Anna university ma8151 engineering mathematics i notes is provided below. The qualifying exam syllabus is divided into six areas. Sambalpur university courses and syllabus 2020 download. General mathematics part i and general mathematics part ii please read the information in this syllabus before proceeding to the course materials. Rgpv syllabus for engineering mathematics 1 mumbai university for full course. It has long been the language of science and technology, and provides a rich source of methods for analyzing and solving problems encountered in the physical world. To access the university of kentucky department of mathematics s syllabi from previous semesters, please choose a course from the list below. The examiners are asked to limit their questions to major quals topics covered in these books. Rowan university department of mathematics syllabus. Undergraduate course syllabus templates below are syllabus templates for some of the undergraduate courses in the department of mathematics and statistics including a generic one for upper division courses. M 1111h college algebra spring semester 2019 course. Ma8251 syllabus engineering mathematics 2 regulation 2017 anna university free download. Both units employ a stepwise logical approach using mathematical reasoning, principles and patterns to develop models, test conjectures and judge validity of arguments and conclusions. This document comprises 4 chapters as described below. Thiruvalluvar university courses and syllabus 2020. Generic elective for non mathematics students 4 papers. In each case, we suggest a book to more carefully define the syllabus. Kolhan university syllabus 2020, pdf revised ba, bsc, b. Csir net syllabus for mathematics is an essential thing to begin up your exam preparation. Syllabus for general mathematics welcome to ma011, ma012. Ma8151 syllabus engineering mathematics 1 ma8151 syllabus engineering mathematics 1 regulation 2017 anna university free download. Please select winter 2020 fall 2019 summer 2019 spring 2019 winter 2019 fall 2018 summer 2018 spring 2018 winter 2018 fall 2017 summer 2017 spring 2017 winter 2017. Engineering mathematics 2 syllabus ma8251 pdf free download. Ma8151 syllabus engineering mathematics 1 regulation 2017. Please note that is just a sample syllabus, actual syllabi for the various sections of the course will likely be different each semester. In addition to this, the applicants can get information about the. Candidates who are looking for the university of calicut entrance exam syllabus 2020 must check this article completely. Mathematics for regular students as is the case with other m. In this page, ma8151 engineering mathematics i m1 syllabus is available in pdf format, hence anna university 1st semester engineering students can download ma8151 syllabus. Noman lbrigs, discrete mathematics, oxford university press, 2003. New syllabus mathematics nsm is a series of textbooks where the inclusion of valuable learning experiences, as well as the integration of reallife applications of learnt concepts serve to engage the hearts and minds of students sitting for the gce olevel examination in mathematics. Mathematics k10 syllabus 4 introduction k10 curriculum board of studies syllabuses have been developed with respect to some overarching views about education. Aspirants who are waiting for the exact tuee syllabus 2020 can go through this post. Each syllabus has its own specific set of aims to guide the design and implementation of the syllabus. There are no prerequisites for math 42, other than high school algebra. Tuee syllabus 2020 pdf download tezpur university entrance exam pattern. Syllabus for discrete mathematics for computer science. Department of mathematics at columbia university new york. The university of toledo department of mathematics and. The qualifying exam syllabus harvard mathematics department. Syllabus traditionally, all mathematics has been divided into three parts. Universities of odisha aims to provide a foundation for pursuing research in. Ese2019 engineering mathematics paper1 analysis target ies this video provides an analysis of engineering mathematics for ese 2019 prelims paper1. Mathematics parti and partii regular scheme are given below. The series covers the new cambridge o level mathematics syllabus d 40244029 for examinations in 2018.1351 312 721 588 370 1418 259 1313 1202 1328 939 232 1472 1284 363 1454 1402 476 496 1515 1208 267 1137 1172 185 81 49 1474 855 1262 239 974 789 1540 873 810 802 1154 1498 1460 308 563 697 695 1399

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http://www.ck12.org/book/CK-12-Middle-School-Math-Concepts-Grade-8/r19/section/3.10/

math

Have you ever tried to figure out a problem involving mileage? Take a look at this situation. On Sunday, Leah walked 4 miles. On Monday, Leah walked one-third as many miles as she walked on Tuesday. She walked a total of 12 miles on those 3 days. Pay attention to this Concept. It will help you to work with fractions. Then you can solve this dilemma successfully. Do you know how to solve this equation that has fractions in it? Let's look at how to do this. Some equations with fractions will also have a set of parentheses in them. To work with these problems, you will need to use the distributive property to simplify the equation. Solve each for the unknown variable. Be sure your answer is in simplest form. Now let's go back to the dilemma at the beginning of the Concept. How far did Leah walk on Monday? Leah walked 2 miles on Monday. the set of whole numbers and their opposites. a set of numbers that includes integers, decimals, fractions, terminating and repeating decimals. These numbers can be written in fraction form. a part of a whole written using a numerator and a denominator. a part of a whole written using place value and a decimal point. a decimal where the digits repeat in a pattern and eventually end. a decimal where the digits eventually end, but where numbers do not repeat in a pattern. Here is one for you to try on your own. Solve for the unknown variable. Be sure that your answer is in simplest form. First, add the numerators of the two fractions with a common denominator. Our work is simpler now. Solving Two-Step Linear Equations with Fractions Directions: Solve each equation.

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http://mathhelpforum.com/calculus/130138-help-problem.html

math

Last edited by Marg7; Feb 22nd 2010 at 01:58 PM. Follow Math Help Forum on Facebook and Google+ Originally Posted by Marg7 Let F(x)= ∫sqrt(t^2 + t) dt (from 1 to 2x) Find: -the domain of F(x) -the limit of F(x) as x approaches 1/2 -the length of the curve y=F(x) for x is greater than or equal to 1 and less than or equal to 2 How would I go about doing these? Thank you! domain ... either , or since the lower limit is , ... View Tag Cloud

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https://ui.adsabs.harvard.edu/abs/2019arXiv190808684V/abstract

math

In this paper we consider the problem of minimising drawdown in a portfolio of financial assets. Here drawdown represents the relative opportunity cost of the single best missed trading opportunity over a specified time period. We formulate the problem (minimising average drawdown, maximum drawdown, or a weighted combination of the two) as a nonlinear program and show how it can be partially linearised by replacing one of the nonlinear constraints by equivalent linear constraints. Computational results are presented (generated using the nonlinear solver SCIP) for three test instances drawn from the EURO STOXX 50, the FTSE 100 and the S&P 500 with daily price data over the period 2010-2016. We present results for long-only drawdown portfolios as well as results for portfolios with both long and short positions. These indicate that (on average) our minimal drawdown portfolios dominate the market indices in terms of return, Sharpe ratio, maximum drawdown and average drawdown over the (approximately 1800 trading day) out-of-sample period.

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https://goprep.co/i-derive-an-expression-for-drift-velocity-of-free-electrons-i-1nlaw6

math

(i) First, We suppose a conductor with an electric field E. Let a free electron experience a force (-eE) in the electric field. Thus, the acceleration of free electron can be written as: E is the electric field as shown in the figure, ‘e’ is the charge on an electron ‘m’ is the mass of the electron. Thus, the velocity of the free charge carrier .i.e. electron in time interval t1 is, v1 = u1 + at1 ……..(2) v1 is the final velocity of the electron after time interval t1 The final velocities for the n charge carriers is supposed to be v2, v3, …. vn. The average velocity or the drift velocity (vd) of the free electrons thus is, vd = (v1 + v2 + v3…. + vn)/ n we put the values of final velocity from (2) to get, ⇒ vd = (u1 + at1 + u2 + at2……..un + atn) / n ⇒ vd = [(u1 + u2 + ….un) + a(t1 + t2 + …..tn)] / n We also know that the electrons were initially at rest, the average initial velocity is thus zero. ⇒ (u1 + u2 + ….un)n = 0 And the total average time taken between two consecutive collisions = (t1 + t2 + t3….. + t4) /n = τ τ is defiend as the relaxation time. vd = at putting the value from (1) we get, ⇒ vd = This is the required drift velocity. (ii) The drift velocity of free electrons in a metallic conductor is inversely proportional to the temperature, it decreases with the increases in temperature as in the metallic conductor the collision between the electrons and ions increases with the increase in the temperature, thus decreasing the relaxation time. Therefore, the drift velocity decreases. Rate this question :

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http://www.orglist.net/archive/2007/0203.html

math

From: Darren Rhodes (darren.rhodes$##$gmail.com) Date: Thu Nov 15 2007 - 09:06:57 EST No. In relation to your question below: does the reaction go to comletion? I've ran systems where I attempt to oxidise a secondary alcohol to a ketone but the reaction didn't go to completion irrespective of the number of molar equivalents of oxidant. Has anyone else observed this phenomenon and if so, do you have a rationale? On 05/11/2007, ricardo mendonca <ricfmendonca$##$gmail.com> wrote: > As anyone run into unwanted chlorination during a Sodium Hypochlorite > (NaClO; BLEACH) oxidation of a secondary alcohol to a ketone? > If yes, have you used any chlorine scanveger? Which one? > References of articles are well apreciated. > I am aware of the use of chlorine scanvegers (2-methyl-2-butene, and alike) > during the Sodium chlorite (NaClO2) oxidation of aldehydes to carbox. acids. > I wonder if anyone have used sulphamic acid (chlorine scavenger) in this > reactions and if it did inhibit chlorination issues. > Thanks in advance > Ricardo Mendonca > ORGLIST - Organic Chemistry Mailing List > Website / Archive / FAQ: http://www.orglist.net > To post a message (TO EVERYBODY) send to everybody$##$orglist.net > To unsubscribe, send to everybody-request$##$orglist.net the message: > unsubscribe your_orglist_password your_address -- Key ID:- 0xB76FE0B9 http://pgpkeys.mit.edu:11371/ http://en.scientificcommons.org/ _______________________________________________ ORGLIST - Organic Chemistry Mailing List Website / Archive / FAQ: http://www.orglist.net To post a message (TO EVERYBODY) send to everybody$##$orglist.net To unsubscribe, send to everybody-request$##$orglist.net the message: unsubscribe your_orglist_password your_address This archive was generated by hypermail 2.1.4 : Thu Feb 18 2010 - 16:51:51 EST

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https://www.wyzant.com/resources/answers/304831/find_the_range

math

I believe that you're intending to deal with the rational algebraic function f(x) = (x+4) / (x+2) which has Domain all Reals except -2. This function has an inverse, and its Range is ALL REALS EXCEPT -2 by virtue of the interchange of variables that is used to derive f-1. I find f-1(x) = -2(x+1) / (x-1) and its domain is all Reals except 1. THEREFORE THE RANGE OF f IS ALL REALS EXCEPT 1. You can verify this by attempting to set f(x) = 1; that equation has no solution.

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https://vanityfairrewards.com/skin-diseases/how-many-moles-of-carbon-dioxide-are-there-in-52-06-g-of-co2.html

math

How many moles of carbon are in CO2? A mole of CO2 molecules (we usually just say “a mole of CO2”) has one mole of carbon atoms and two moles of oxygen atoms. How many moles are in CO2 G? The molecular mass of carbon dioxide is 44.01amu. The molar mass of any compound is the mass in grams of one mole of that compound. One mole of carbon dioxide molecules has a mass of 44.01g, while one mole of sodium sulfide formula units has a mass of 78.04g. The molar masses are 44.01g/mol and 78.04g/mol respectively. How many moles are in 28.0 g of CO2? Mol in 28 g CO2 = 28 g / 44 g/mol = 0.64 mol – 2 significant digits. How many moles are in 44g of CO2? Using the formula number of moles = Mass/Mr 44/44=1 mole of CO2 present. (Mr of carbon dioxide is (2*16)+12=44 Now times by Abogadros constant: 1* 6.022*10^23=6.022*10^23 molecules of CO2 are present. How many moles are there in 12g of CO2? 12.00 g C-12 = 1 mol C-12 atoms = 6.022 × 1023 atoms • The number of particles in 1 mole is called Avogadro’s Number (6.0221421 x 1023). How many moles are there in 330 g of carbon dioxide? The answer is 44.0095. We assume you are converting between grams CO2 and mole. You can view more details on each measurement unit: molecular weight of CO2 or mol This compound is also known as Carbon Dioxide. The SI base unit for amount of substance is the mole. How do you calculate moles of CO2? Calculate the number of moles of CO2 by the formula n=PV/RT, where P is the pressure from Step 3, V is the volume from Step 2, T is the temperature from Step 1 and R is a proportionality constant equal to 0.0821 L atm / K mol. How many moles of CO2 are produced? If the mole ratio is 1 to 2 (where 1 mole of oxygen reacts with a reactant and yields 2 moles of carbon dioxide), then 2 x 0.2732 moles of carbon dioxide will be produced. How do I calculate moles? How to find moles? - Measure the weight of your substance. - Use a periodic table to find its atomic or molecular mass. - Divide the weight by the atomic or molecular mass. - Check your results with Omni Calculator. How many moles is MgCl2? Explanation: The molar mass (mass of one mole) of magnesium chloride, MgCl2 , is 95.211 g/mol . To calculate the number of moles of MgCl2 in 4.75 g , divide the given mass by the molar mass.

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https://umj.imath.kiev.ua/index.php/umj/article/view/2879

math

On the modularity of a lattice of $τ$-closed $n$-ultiply $ω$-composite formations AbstractLet $n ≥ 0$, let $ω$ be a nonempty set of prime numbers and let $τ$ be a subgroup functor (in Skiba’s sense) such that all subgroups of any finite group $G$ contained in $τ (G)$ are subnormal in $G$. It is shown that the lattice of all $τ$-closed $n$-multiply $ω$-composite formations is algebraic and modular. How to Cite Vorob’ev, N. N., and A. A. Tsarev. “On the Modularity of a Lattice of $τ$-Closed $n$-Ultiply $ω$-Composite Formations”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 62, no. 4, Apr. 2010, pp. 453–463, https://umj.imath.kiev.ua/index.php/umj/article/view/2879.

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https://play.google.com/store/apps/details?id=nz.co.aztecinfo&referrer=utm_source%3Dappbrain

math

Good, but i prefer "iMargin" calculator more It is good but some difficult. I prefer more simple and quickly calculator iMargin. Would you please make function "clear all fields on shake" like in iMargin calculator? Flawless, relevant, useful Simple, thoughtful it does what it says and has the extra features if you need them. Every salesman should use this tool. Best one out there! I would give 5 but only when the mistakes are fixed. The 1st line is gross margin%. 2nd is Markup% and 3rd is gross profit. It currently says 1st % gross profit, 2nd is %margin and last line is markup per unit. Excellent app Total time saver for over worked chefs, I just did an entire menu costing in half the time. Thank you so much developer Not a margin calculator As best as I can tell it only calculates markup which is a different calculation. Excellent, I work in the retail industry. I calc margin and penny profit all day. Works like a charm!!!!!!

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https://www.supergb.com/cbt/assessment/d30d46dc-9edb-4a60-9550-cae92d811cd2/question/fae21659-093d-425b-a16b-81bc96f92f7e

math

Question 1 Report Which of the following gives the point of intersection of the graph y = x2 and y = x + 6 shown above? The problem is asking us to find the point of intersection of the two graphs y = x2 and y = x + 6. This can be done by solving the equations simultaneously. We need to find the values of x and y that satisfy both equations. We can do this by substituting y = x + 6 for y in the equation y = x2, giving us: x + 6 = x2 Rearranging this equation gives us: x2 - x - 6 = 0 We can factor this quadratic equation to obtain: (x - 3)(x + 2) = 0 Thus, the solutions are x = 3 or x = -2. To find the corresponding values of y, we can substitute these values of x into either of the original equations. For example, if we use y = x + 6, we get: When x = 3, y = 3 + 6 = 9, giving us the point (3, 9). When x = -2, y = -2 + 6 = 4, giving us the point (-2, 4). Therefore, the point of intersection of the two graphs is (3, 9) and (-2, 4).

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https://forums.fishusa.com/Message/402840-New-to-the-area/

math

New to the area Hello all, my names steve, and I'm a 20 year old fisherman who just moved to the area. I live in Williamsport in lycoming county, and I need some help. I've heard that there's amazing fishing up here, but I'm having trouble finding it. If someone could please help me by telling me where the local fishing spots and where the best fishing spots around are, it would be greatly appreciated. Also, I don't really know the area that well, so if you could help me figure out how to get to the spots, that would be great, thanks.

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https://www.sarthaks.com/223130/block-of-mass-is-kept-over-fixed-smooth-wedge-block-is-attached-to-sphere-same-mass-through

math

A block of mass m is kept over a fixed smooth wedge. Block is attached to a sphere of same mass through fixed massless pullies P1 and P2. Sphere is dipped inside the water as shown. If specific gravity of material of sphere is 2. Find the acceleration of sphere.

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https://www.quantamagazine.org/authors/kevin-hartnett/page/5

math

Computer Scientists Attempt to Corner the Collatz Conjecture A powerful technique called SAT solving could work on the notorious Collatz conjecture. But it’s a long shot. How Physics Found a Geometric Structure for Math to Play With Symplectic geometry is a relatively new field with implications for much of modern mathematics. Here’s what it’s all about. New Geometric Perspective Cracks Old Problem About Rectangles While locked down due to COVID-19, Joshua Greene and Andrew Lobb figured out how to prove a version of the “rectangular peg problem.” The ‘Useless’ Perspective That Transformed Mathematics Representation theory was initially dismissed. Today, it’s central to much of mathematics. In Mathematics, It Often Takes a Good Map to Find Answers Mathematicians try to figure out when problems can be solved using current knowledge — and when they have to chart a new path instead. Mathematician Measures the Repulsive Force Within Polynomials Vesselin Dimitrov’s proof of the Schinzel-Zassenhaus conjecture quantifies the way special values of polynomials push each other apart.

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https://www.coursehero.com/file/5984956/Well-first-you-can-make-the-odds-of-that-happening-as-small/

math

Unformatted text preview: d Leonard Adleman—it has since withstood years of extensive cryptanalysis. Although the cryptanalysis neither proved nor disproved RSA’s security, it does suggest a confidence level in the algorithm. Table 19.1 Foreign Merkle-Hellman Knapsack Patents Country Belgium Netherlands Great Britain Germany Sweden Number 871039 7810063 2006580 2843583 7810478 Date of Issue 5 Apr 1979 10 Apr 1979 2 May 1979 10 May 1979 14 May 1979 France Germany Germany Canada Great Britain Switzerland Italy 2405532 2843583 2857905 1128159 2006580 63416114 1099780 8 Jun 1979 3 Jun 1982 15 Jul 1982 20 Jul 1982 18 Aug 1982 14 Jan 1983 28 Sep 1985 RSA gets its security from the difficulty of factoring large numbers. The public and private keys are functions of a pair of large (100 to 200 digits or even larger) prime numbers. Recovering the plaintext from the public key and the ciphertext is conjectured to be equivalent to factoring the product of the two primes. To generate the two keys, choose two random large prime numbers, p and q. For maximum security, choose p and q of equal length. Compute the product: n = pq Then randomly choose the encryption key, e, such that e and (p - 1)(q - 1) are relatively prime. Finally, use the extended Euclidean algorithm to compute the decryption key, d, such that ed a 1 mod (p - 1)(q - 1) In other words, d = e-1 mod ((p - 1)(q - 1)) Note that d and n are also relatively prime. The numbers e and n are the public key; the number d is the private key. The two primes, p and q, are no longer needed. They should be discarded, but never revealed. To encrypt a message m, first divide it into numerical blocks smaller than n (with binary data, choose the largest power of 2 less than n). That is, if both p and q are 100-digit primes, then n will have just under 200 digits and each message block, mi , should be just under 200 digits long. (If you need to encrypt a fixed number of blocks, you can pad them with a few zeros on the left to ensure that they will always be less than n.) The encr... View Full Document - Fall '10 - Cryptography, Bruce Schneier, Applied Cryptography, EarthWeb, Search Search Tips

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https://www.britannica.com/biography/Carl-Friedrich-Gauss

math

Gauss was the only child of poor parents. He was a calculating prodigy with a gift for languages. His teachers and his devoted mother recommended him to the duke of Brunswick in 1791, who granted him financial assistance to continue his education locally and then to study mathematics at the University of Göttingen. What awards did Carl Friedrich Gauss win? Gauss won the Copley Medal, the most prestigious scientific award in the United Kingdom, given annually by the Royal Society of London, in 1838 “for his inventions and mathematical researches in magnetism.” For his study of angle-preserving maps, he was awarded the prize of the Danish Academy of Sciences in 1823. How was Carl Friedrich Gauss influential? Gauss wrote the first systematic textbook on algebraic number theory and rediscovered the asteroidCeres. He published works on number theory, the mathematical theory of map construction, and many other subjects. After Gauss’s death in 1855, the discovery of many novel ideas among his unpublished papers extended his influence into the remainder of the century. Carl Friedrich Gauss, original name Johann Friedrich Carl Gauss, (born April 30, 1777, Brunswick [Germany]—died February 23, 1855, Göttingen, Hanover), German mathematician, generally regarded as one of the greatest mathematicians of all time for his contributions to number theory, geometry, probability theory, geodesy, planetary astronomy, the theory of functions, and potential theory (including electromagnetism). Gauss was the only child of poor parents. He was rare among mathematicians in that he was a calculating prodigy, and he retained the ability to do elaborate calculations in his head most of his life. Impressed by this ability and by his gift for languages, his teachers and his devoted mother recommended him to the duke of Brunswick in 1791, who granted him financial assistance to continue his education locally and then to study mathematics at the University of Göttingen from 1795 to 1798. Gauss’s pioneering work gradually established him as the era’s preeminent mathematician, first in the German-speaking world and then farther afield, although he remained a remote and aloof figure. Gauss’s first significant discovery, in 1792, was that a regular polygon of 17 sides can be constructed by ruler and compass alone. Its significance lies not in the result but in the proof, which rested on a profound analysis of the factorization of polynomial equations and opened the door to later ideas of Galois theory. His doctoral thesis of 1797 gave a proof of the fundamental theorem of algebra: every polynomial equation with real or complex coefficients has as many roots (solutions) as its degree (the highest power of the variable). Gauss’s proof, though not wholly convincing, was remarkable for its critique of earlier attempts. Gauss later gave three more proofs of this major result, the last on the 50th anniversary of the first, which shows the importance he attached to the topic. Gauss’s recognition as a truly remarkable talent, though, resulted from two major publications in 1801. Foremost was his publication of the first systematic textbook on algebraic number theory, Disquisitiones Arithmeticae. This book begins with the first account of modular arithmetic, gives a thorough account of the solutions of quadratic polynomials in two variables in integers, and ends with the theory of factorization mentioned above. This choice of topics and its natural generalizations set the agenda in number theory for much of the 19th century, and Gauss’s continuing interest in the subject spurred much research, especially in German universities. The second publication was his rediscovery of the asteroidCeres. Its original discovery, by the Italian astronomer Giuseppe Piazzi in 1800, had caused a sensation, but it vanished behind the Sun before enough observations could be taken to calculate its orbit with sufficient accuracy to know where it would reappear. Many astronomers competed for the honour of finding it again, but Gauss won. His success rested on a novel method for dealing with errors in observations, today called the method of least squares. Thereafter Gauss worked for many years as an astronomer and published a major work on the computation of orbits—the numerical side of such work was much less onerous for him than for most people. As an intensely loyal subject of the duke of Brunswick and, after 1807 when he returned to Göttingen as an astronomer, of the duke of Hanover, Gauss felt that the work was socially valuable. Similar motives led Gauss to accept the challenge of surveying the territory of Hanover, and he was often out in the field in charge of the observations. The project, which lasted from 1818 to 1832, encountered numerous difficulties, but it led to a number of advancements. One was Gauss’s invention of the heliotrope (an instrument that reflects the Sun’s rays in a focused beam that can be observed from several miles away), which improved the accuracy of the observations. Another was his discovery of a way of formulating the concept of the curvature of a surface. Gauss showed that there is an intrinsic measure of curvature that is not altered if the surface is bent without being stretched. For example, a circular cylinder and a flat sheet of paper have the same intrinsic curvature, which is why exact copies of figures on the cylinder can be made on the paper (as, for example, in printing). But a sphere and a plane have different curvatures, which is why no completely accurate flat map of the Earth can be made. Are you a student? Get Britannica Premium for only $24.95 - a 67% discount! Gauss published works on number theory, the mathematical theory of map construction, and many other subjects. In the 1830s he became interested in terrestrial magnetism and participated in the first worldwide survey of the Earth’s magnetic field (to measure it, he invented the magnetometer). With his Göttingen colleague, the physicist Wilhelm Weber, he made the first electric telegraph, but a certain parochialism prevented him from pursuing the invention energetically. Instead, he drew important mathematical consequences from this work for what is today called potential theory, an important branch of mathematical physics arising in the study of electromagnetism and gravitation. Gauss also wrote on cartography, the theory of map projections. For his study of angle-preserving maps, he was awarded the prize of the Danish Academy of Sciences in 1823. This work came close to suggesting that complex functions of a complex variable are generally angle-preserving, but Gauss stopped short of making that fundamental insight explicit, leaving it for Bernhard Riemann, who had a deep appreciation of Gauss’s work. Gauss also had other unpublished insights into the nature of complex functions and their integrals, some of which he divulged to friends. In fact, Gauss often withheld publication of his discoveries. As a student at Göttingen, he began to doubt the a priori truth of Euclidean geometry and suspected that its truth might be empirical. For this to be the case, there must exist an alternative geometric description of space. Rather than publish such a description, Gauss confined himself to criticizing various a priori defenses of Euclidean geometry. It would seem that he was gradually convinced that there exists a logical alternative to Euclidean geometry. However, when the Hungarian János Bolyai and the Russian Nikolay Lobachevsky published their accounts of a new, non-Euclidean geometry about 1830, Gauss failed to give a coherent account of his own ideas. It is possible to draw these ideas together into an impressive whole, in which his concept of intrinsic curvature plays a central role, but Gauss never did this. Some have attributed this failure to his innate conservatism, others to his incessant inventiveness that always drew him on to the next new idea, still others to his failure to find a central idea that would govern geometry once Euclidean geometry was no longer unique. All these explanations have some merit, though none has enough to be the whole explanation. Another topic on which Gauss largely concealed his ideas from his contemporaries was elliptic functions. He published an account in 1812 of an interesting infinite series, and he wrote but did not publish an account of the differential equation that the infinite series satisfies. He showed that the series, called the hypergeometric series, can be used to define many familiar and many new functions. But by then he knew how to use the differential equation to produce a very general theory of elliptic functions and to free the theory entirely from its origins in the theory of elliptic integrals. This was a major breakthrough, because, as Gauss had discovered in the 1790s, the theory of elliptic functions naturally treats them as complex-valued functions of a complex variable, but the contemporary theory of complex integrals was utterly inadequate for the task. When some of this theory was published by the Norwegian Niels Abel and the German Carl Jacobi about 1830, Gauss commented to a friend that Abel had come one-third of the way. This was accurate, but it is a sad measure of Gauss’s personality in that he still withheld publication. Gauss delivered less than he might have in a variety of other ways also. The University of Göttingen was small, and he did not seek to enlarge it or to bring in extra students. Toward the end of his life, mathematicians of the calibre of Richard Dedekind and Riemann passed through Göttingen, and he was helpful, but contemporaries compared his writing style to thin gruel: it is clear and sets high standards for rigour, but it lacks motivation and can be slow and wearing to follow. He corresponded with many, but not all, of the people rash enough to write to him, but he did little to support them in public. A rare exception was when Lobachevsky was attacked by other Russians for his ideas on non-Euclidean geometry. Gauss taught himself enough Russian to follow the controversy and proposed Lobachevsky for the Göttingen Academy of Sciences. In contrast, Gauss wrote a letter to Bolyai telling him that he had already discovered everything that Bolyai had just published. After Gauss’s death in 1855, the discovery of so many novel ideas among his unpublished papers extended his influence well into the remainder of the century. Acceptance of non-Euclidean geometry had not come with the original work of Bolyai and Lobachevsky, but it came instead with the almost simultaneous publication of Riemann’s general ideas about geometry, the Italian Eugenio Beltrami’s explicit and rigorous account of it, and Gauss’s private notes and correspondence.

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https://byjus.com/ncert-solutions-for-class-9-maths-chapter-13-surface-area-and-volume-ex-13-1/

math

NCERT solutions for class 9 Maths Chapter 13 – Surface Areas and Volumes Exercise 13.1, includes the solved problems from the NCERT textbook. The solutions are available in PDF format and students can download effortlessly. The NCERT solutions are created by maths subject experts along with proper geometric figures and explanations in a step by step procedure for good understanding. The collection of all the solutions in NCERT solutions for class 9 maths is as per the latest NCERT syllabus and guidelines of the CBSE board and it aims to help the students to score good marks in board examinations. Download PDF of NCERT Solutions for Class 9 Maths Chapter 13 – Surface Areas and Volumes Exercise 13.1 Access Answers of Maths NCERT Class 9 Maths Chapter 13 – Surface Areas and Volumes Exercise 13.1 Access other exercise solutions of class 9 Maths Chapter 13 – Surface Areas and Volumes Exercise 13.2 solution (8 questions) Exercise 13.3 solution (9 questions) Exercise 13.4 solution (5 questions) Exercise 13.5 solution (5 questions) Exercise 13.6 solution (8 questions) Exercise 13.7 solution (9 questions) Exercise 13.8 solution (10 questions) Exercise 13.9 solution (3 questions) NCERT Solutions for class 9 Maths Chapter 13 – Surface Areas and Volume Exercise 13.1 Exercise 13.1 of class 9 maths consists of problems which cover the concepts like the surface area of cube and cuboid. It involves application level real-time problems that students to think and apply the relevant formula It also explains how six rectangular pieces to cover the complete outer surface of the cuboid and how the surface area of a cuboid and cube is found. Learn the entire NCERT solutions for class 9 Maths Chapter 13 along with other learning materials, notes provided by BYJU’S. The problems are solved in a detailed way with relevant formulas and figures to score well in exams. Key Features of NCERT Solutions for class 9 Maths Chapter 13 – Surface Areas and Volume Exercise 13.1 - These NCERT Solutions let you solve and revise all questions of Exercise 13.1. - Stepwise solutions given by our subject expert teachers will help you to secure more marks. - It follows NCERT guidelines which help in preparing the students accordingly. - It contains all the important questions that are most expected for the examination.

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https://mikemccarthycomedy.com/trigonometry-how-to-solve-876

math

Input math problem We'll provide some tips to help you select the best Input math problem for your needs. We can solving math problem. The Best Input math problem There are a lot of Input math problem that are available online. To find the domain and range of a given function, we can use a graph. For example, consider the function f(x) = 2x + 1. We can plot this function on a coordinate plane: As we can see, the function produces valid y-values for all real numbers x. Therefore, the domain of this function is all real numbers. The range of this function is also all real numbers, since the function produces valid y-values for all real numbers x. To find the domain and range of a given function, we simply need to examine its graph and look for any restrictions on the input (domain) or output (range). In addition, the website provides a forum for students to ask questions and receive help from other users. Whether you are looking for a way to improve your child's math skills or simply want to provide them with a fun and educational activity, web math is an excellent choice. College algebra is the study of numbers, graphs, and equations. Functions are a way of describing relationships between certain variables in an equation. In college algebra, we use functions to model real-world situations. For example, we might use a function to model the relationship between the amount of money we spend on gas and the number of miles we can drive. Functions can be linear or nonlinear. Linear functions have a straight line graph, while nonlinear functions have a curved line graph. College algebra is all about understanding how functions work and using them to solve problems. Imagine being able to simply take a picture of a math word problem and have the answer pop up on your screen almost instantaneously. That's what one new app promises to do. The app, called PhotoMath, uses the camera on your smartphone or tablet to take a picture of a math problem and then displays the answer. Just point your camera at a problem and PhotoMath will do the rest. The app can solve problems ranging from simple addition and subtraction to more complex equations involving fractions and decimals. It can even handle problems that require multiple steps, such as long division. And if you're not satisfied with the answer it gives you, PhotoMath also provides step-by-step instructions for how to solve the problem. PhotoMath is still in its early stages, so it doesn't always get things right. But it shows promise as a tool that could one day make solving math problems a breeze. So if you're struggling with a math problem, why not give PhotoMath a try? It just might be the answer you're looking for. Solving by completing the square is a method that can be used to solve certain types of equations. The goal is to transform the equation into one that has a perfect square on one side, which can then be solved using the quadratic formula. This technique can be helpful when other methods, such as factoring, fail to provide a solution. To complete the square, start by taking the coefficient of the x^2 term and squaring it. This number will be added to both sides of the equation. Next, divide both sides of the equation by this number. The resulting equation should have a perfect square on one side. Finally, apply the quadratic formula to solve for x. With a little practice, solving by completing the square can be a helpful tool in solving equations. Instant help with all types of math It's just more than I can describe. It's been of great help to me in every way possible. Thanks to the developers. I've not had an experience with ads while using the app. I'd recommend it to everyone out there either a student parent or teacher that needs help in getting certain calculations done in no time with insightful explanation just download #the app. I love it, best wat to check your work or even show you wat to do if you don't understand what’s going on. When taking pictures I have no problems, my friend has problems because he has a low pixel’s camera, the more your pixels the better the photo. I love the app and would recommend it to everyone out there struggling. Five stars from me

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CC-MAIN-2022-49

http://andersonformemphis.com/education/microeconomics-theory-pdf.php

math

Main / Education / Microeconomics theory pdf Microeconomics theory pdf Name: Microeconomics theory pdf File size: 957mb 18 Aug Notes on Microeconomic Theory ver: Aug. 3 The Traditional Approach to Consumer Theory. Basics of Preference Relations. Advanced. Microeconomic. Theory. THIRD EDITION. GEOFFREY A. JEHLE. Vassar College. PHILIP J. RENY. University of Chicago. Sandee Milewski. Printer: West Group. Eagan, MN. Microeconomic Theory. Basic Principles and Extensions. Tenth Edition. Walter Nicholson Christopher Snyder. In Micro II, you learn — through general equilibrium and game theory — how .. It turns out that correspondences are very common in microeconomics, even. Lecture Notes1. Microeconomic Theory. Guoqiang TIAN. Department of Economics. Texas A&M University. College Station, Texas ([email protected] edu). PDF | On Apr 29, , Gholamreza keshavarz haddad and others published Microeconomics theory. 26 Aug INTRODUCTION TO MICROECONOMIC THEORY. 1. THE SCIENCE OF ECONOMICS. Economics is the study of choice under conditions of. The 10th edition of Microeconomic Theory: Basic Principles and Extensions For any random variable, its probability density function (PDF) shows the. David A. Dilts, Introduction to Microeconomics, E Fort Wayne: Economic theory - relies upon principles to analyze behavior of economic agents. e. These notes are prepared for the Microeconomic courses I teach at the Nicholson, W., and C. M. Snyder (): Microeconomic theory: basic principles. Lecture Notes in. Microeconomic Theory Lecture notes in microeconomic theory: the economic agent / andersonformemphis.com pdf.).

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CC-MAIN-2019-18

http://www.docstoc.com/docs/122946015/SOLUTIONS---CHAPTER-30

math

EXAMPLE SOLUTIONS – Topic 8: ELECTROMAGNETIC INDUCTION 1) A rod 4 meters in length is placed in a magnetic field at right angles to the direction of B which has a magnitude of 0.3 Tesla. If v the rod is moved with a speed of 3 m/sec in a direction perpendicular to its length and perpendicular to B, what emf is induced across the ends of the rod? Draw a figure and indicate the direction of the induced emf. B Solution: We first determine the direction of the induced Emf in the rod. We can do this either by Lenz's Law, or in this case by using q v B. If we consider a '+' charge in the rod, this is moving to the left. Thus v B is downward, and the bottom of the rod will become the positive end of the Emf. The Emf produced is given by: E = (F / q) d s (1 / q) Fmag d v B d vx B Hence: E = B v d = (.3)(3)(4) = 3.6 Volts. 2) A loop of wire of area 0.5 m2 is positioned between the pole faces of a large electromagnet so that the perpendicular to the plane of the loop makes an angle of 30o with respect to the magnetic field direction. The magnet is turned on, and a final magnetic induction of 30 Teslas is reached within 200 msec. What is the average emf induced in the coil during this time? Solution: We draw the loop (our loop actually has only one turn). Applying Lenz's Law we have the flux increasing since the external field is increasing. Hence, y B loop must be opposite B . Applying the right hand rule 30 we have the current within the loop from 'A' to 'B'. B Hence, in an external circuit the current would be from 'B' to 'A'. This makes point 'B' the positive terminal of A B loop the Emf. From Faraday's Law we have: z B x Eave = /t . Since the flux is B A cos 30 then E ave = A (B/t) cos 30 = (.5)(30)(.866)/(.2) = 65.4 Volts. 3) A rod of length 1 meter is allowed to roll down the incline shown. The magnetic induction is 0.2 T, and is perpendicular to the plane of the loop. The v resistance R is 10 ohms. The resistance of the rod and the rails may be neglected. R 370 a) In terms of 'v' the speed of the rod down the plane, determine the emf induced in the rod, and hence the current produced in the loop. b) In terms of v determine the magnitude and direction of the magnetic force exerted on the rod. c) Let g = 10 m/sec2. If the mass of the rod is 20 gm, determine the terminal speed of the rod. Solution: We first apply Lenz's Law to determine the direction of the induced current. Since the area is decreasing, the flux through the loop is decreasing. v Hence, B ind must be in the same direction as B. Applying the right hand rule we have the current as shown. For a given velocity I B E(v) = B v d where 'd' is the length of the rod. B ind Thus the current in the loop will also depend on 'v'. I(v) = E/R = (B v d)/R . Since there is a current in the rod, then there will be a magnetic force acting on the rod. Looking at the plane sideways, we have the current coming out of the rod. Hence: N F w = I L B acts up the plane. # From Newton's 2nd Law we then have: I B Fx = mg sin 37 - F w = m a x and mg F y = N - mg cos 37 = 0 The magnetic force is F w = I d B sin 90 = I d B = (d B)2 vx/R . We see that as vx increases, the force up the plane increases as well. Hence, a terminal speed will be reached when a x 0. That is: F w = mg sin 37 (d B)2 vf /R = mg sin 37 . Solving for v f v f = m g R sin 37/(B d)2 = (20 x 10-3)(10)(.6)/(.2)2 = 30 m/sec. 4) The coil shown consists of 100 turns of radius 4 cm. y The magnetic field is constant and has a value of 0.6 T. The coil is initially situated as shown, and is then rotated 90o so that the plane of the coil is parallel to the magnetic field. This rotation takes 0.2 seconds. a) What is the average emf generated in the coil during b) What is the direction of the induced emf? z B x Solution: We draw the loop (our loop actually has more turns) looking down the z-axis. Applying Lenz's Law we I have the flux decreasing since the flux is initially a B maximum amount. Hence, B loop must be the same direction A A as B . Applying the right hand rule we have the current within the loop from 'B' to 'A'. Hence, in an external circuit B the current would be from 'A' to 'B'. This makes point 'A' the B loop positive terminal of the Emf. From Faraday's Law we have: Eave = /t The final flux is zero, and the initial flux is N B A = (100)(.6)()(4 x 10-2)2 = 0.3 Webers. E ave = /t = (.3/(.2) = 1.5 Volts. 5) A shunt wound dc motor built to operate on 120 volts will draw 24 amps when started, but only 5 amps when running at its rated speed. If the field windings have a resistance of 30 ohms, what is the mechanical power developed by the motor? The circuit for a shunt wound motor is as shown. The basic equations for this circuit are: (a) I = If + Ia If (b) Vab = If Rf motor IA E (c) Vab = Ia Ra + E b RA When the motor starts there is no back emf. Hence, the current (24 A) is determined by the combined resistance in the field and armature windings. For the field windings, we have, using equation (b): If = V ab/Rf = (120)/(30) = 4 A . The total resistance of the 2 coils is: R = Vab/I = (120)/(24) = 5 ohms. Thus: 1/R = 1/Rf + 1/Ra 1/Ra = (1/5) - (1/30) = (1/6) or Ra = 6 ohms. When the motor is running we then have: Ia = I - If = 5 - 4 = 1 A. Now applying equation (c): E b = Vab - Ia Ra = 120 - (1)(6) = 144 V. The mechanical power developed is: Pmech = Ia E b = (1)(114) = 114 W.

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http://www.maths.qmul.ac.uk/~dstark/bell.html

math

Oil production models with normal rate curves Hubbert fitted the rate of U.S.A. oil production with logistic curves. Deffeyes says that the normal curve gives a better fit. As far as I know, there has previously been no theoretical justification of these fittings. In my paper Oil production models with normal rate curves conditions ensuring approximately normal rate of production curves are established. It has been accepted to appear in the journal Probability in the Engineering and Informational Sciences. Here is the abstract of the paper: The normal curve has been used to fit the rate of both world and U.S.A. oil production. In this paper we give the first theoretical basis for these curve fittings. It is well known that oil field sizes can be modelled by independent samples from a lognormal distribution. We show that when field sizes are lognormally distributed, and the starting time of the production of a field is approximately a linear function of the logarithm of its size, and production of a field occurs within a small enough time interval, then the resulting total rate of production is close to being a normal curve. We call the total rate of production the sum of the rates of production of the fields constituting a given area. The main idea is that the rates of production of individual fields does not matter much in obtaining an approximately normal total rate of production curve. What matters, assuming the time it takes to produce individual fields is not too long, is the distribution of field sizes and the location in time of Next, I will explain what is meant in the abstract. After that, I will make some remarks about the model in the paper. What is meant by a lognormal distribution? A normal distribution is the familiar bell-shaped curve. A lognormal distribution obtained by a simple transformation of the normal distribution: if X is a normally distributed random variable, then eX is lognormally distributed. Here is the lognormal distribution associated with the normal Lognormal distributions have been used to model the distribution of the oil field sizes in a given area. Moreover, the lognormal distribution is fundamental to the Black-Scholes model of the stock market used in the analysis of derivatives. (Here we are using it for something more sensible.) We will suppose that oil field sizes are given by independent samples from a lognormal distribution. Next we suppose that the production of oil from field of size x occurs approximately at time -a log(x) + b, where a>0 and b are constants. More specifically, we suppose that all the oil produced from a field of size x occurs in the time interval ranging from -a log(x) + b -L to -a log(x) + b + L, where L>0 is Under these assumptions, the rate of oil production converges to a curve which is close to being normal. The "converging" bit means that the total rate of production of the first n fields divided by the total amount of oil ever produced by the first n fields tends to a limit curve as n tends to infinity. What does "close to normal" mean? Let Fn(t) be the amount of oil produced by the first n fields up to time t, divided by the total amount of oil ever produced by the first n fields. Suppose that the lognormal distribution describing the field sizes is obtained from a normal distribution with standard deviation s. Let F(t) be the function you would have corresponding to Fn(t) if the rate of production was exactly normal. It turns out that the normal distribution corresponding to F(t) has standard deviation roughly equal to S = as. where the maximum is taken over all time points t. Then, when n is large enough, Dn < L/ S. Thus, when L/S is small, the rate of production is close to being normal in the sense that Dn is small for n large enough. Note that L can be large and Fn(t) still be close to normal, as long as L/S is small. Here are some concluding comments on the model. - The model could be taken as applying only to fields below a certain For example, the largest field in the U.S.A. is Prudhoe Bay, which started production later than one would expect from its size as a consequence of its location in the arctic. Prudhoe Bay skews the total rate of production curve of the U.S.A. to the right, though not enough to move the peak total rate of production away from 1970. On the other hand, if a few smaller fields were produced earlier than one would expect from their sizes, they would not skew the total rate of production curve by much. - The condition that oil produced from a field of size x occurs in the time interval -a log(x) + b -L to -a log(x) + b + L probably does not need to hold precisely for the approximation to hold. What is intuitively important is that production is concentrated around -a log(x) + b. - It would be most interesting to have empirical evidence as to whether this model describes actual oil production in some area or areas. This should hold when the production of fields of size x is centred about f(x)=-a log(x) + b for some constants a>0 and b. If such evidence exists, then it would be desirable to find some explanation for the appearance of the function f(x). - The total rate of production curve is approximately normal for U.S.A. and world oil production. For many other areas, such as the North Sea, it is not. This could be because the larger areas have a wider range of field sizes and because their total rate of production curves have greater width (which in the model is roughly equal compared to the time intervals individual fields are in production (which in the model is represented by L). - The function -a log(x) +b implies that the smallest fields will be produced indefinitely far into the future; any reasonable model producing a bell shaped curve would have this feature. This is probably an unrealistic Could this be part of the reason that the current rate of oil production in the U.S.A. is higher than was predicted by Hubbert? Another reason could be delayed production from large fields such as Prudhoe Bay. - We have investigated lognormally distributed field sizes together with normal total production curves for the reason that the analysis seemed natural and elegant. Other combinations of field size distributions and classes of total production curves could also be studied, for example with field size determined by independent samples from a Pareto distribution and lognormal rate of production curves. You can get in touch with me at D.S.Stark@maths.qmul.ac.uk

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https://calculators.appzend.net/?q=Treat+Calculator&kind=financial

math

Wonder how much you could save by not buying coffee, candy bar, or one of your favorite regular “treats” that you indulge yourself with on a routine basis? Enter the cost amount and how often you indulge yourself, along with the interest you expect to return on the amounts of the treat costs that you invest. Find out how much you could not only save, but make by investing those funds! How to Calculate Treat Let's be honest - sometimes the best treat calculator is the one that is easy to use and doesn't require us to even know what the treat formula is in the first place! But if you want to know the exact formula for calculating treat then please check out the "Formula" box above.

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CC-MAIN-2024-18

https://imperialglamourbeautybox.com/qa/why-is-e-everywhere.html

math

- How is e value calculated? - What is e function? - Why is e called a natural number? - How do you use e in Excel? - What does E to the negative power mean? - What is the formula of E? - Is E X always positive? - What is E used for in real life? - Where does e occur in nature? - What’s the value of E? - What is E in log? - What does the weird e mean in math? - Why does E exist in math? - What is E to zero? - What is E used for in math? - What is the value of E Power 0? - How do you read E numbers? - Why is e so special? - Can e ever be 0? - What is E to the infinity power? - What does the E mean in an exponential equation? How is e value calculated? We’ve learned that the number e is sometimes called Euler’s number and is approximately 2.71828. Like the number pi, it is an irrational number and goes on forever. The two ways to calculate this number is by calculating (1 + 1 / n)^n when n is infinity and by adding on to the series 1 + 1/1!. What is e function? In mathematics, E-functions are a type of power series that satisfy particular arithmetic conditions on the coefficients. They are of interest in transcendental number theory, and are more special than G-functions. Why is e called a natural number? of 2.718. It was that great mathematician Leonhard Euler who discovered the number e and calculated its value to 23 decimal places. … Its properties have led to it as a “natural” choice as a logarithmic base, and indeed e is also known as the natural base or Naperian base (after John Napier). How do you use e in Excel? =EXP(value) gives the result of e value. For example, to find the value of , where x is to be taken from cell A2 , you would use the formula =EXP(2*A2-1) . (In other words, whatever is in the exponent goes in the parentheses.) What does E to the negative power mean? Prism switches to scientific notation when the values are very larger or very small. For example: 2.3e-5, means 2.3 times ten to the minus five power, or 0.000023. 4.5e6 means 4.5 times ten to the sixth power, or 4500000 which is the same as 4,500,000. What is the formula of E? The number e is an important mathematical constant, approximately equal to 2.71828 . When used as the base for a logarithm, we call that logarithm the natural logarithm and write it as lnx . Is E X always positive? See, e is a positive number which is approximately equal to 2.71828. So e to the power anything ( be it a fraction,decimal,negative integer,positive integer,etc.) … Value of ‘e’ is positive i.e. approximately 2.71828. It implies e^x is always positive for any value of x. What is E used for in real life? Euler’s number, e , has few common real life applications. Instead, it appears often in growth problems, such as population models. It also appears in Physics quite often. As for growth problems, imagine you went to a bank where you have 1 dollar, pound, or whatever type of money you have. Where does e occur in nature? Yes, the number e does have physical meaning. It occurs naturally in any situation where a quantity increases at a rate proportional to its value, such as a bank account producing interest, or a population increasing as its members reproduce. What’s the value of E? 2.71828The Constant e. What is e? “e” is a numerical constant that is equal to 2.71828. Just as pi (3.14159) is a numerical constant that occurs whenever the circumference of a circle is divided by its diameter. What is E in log? The natural logarithm of a number is its logarithm to the base of the mathematical constant e, where e is an irrational and transcendental number approximately equal to 2.718281828459. The natural logarithm of x is generally written as ln x, loge x, or sometimes, if the base e is implicit, simply log x. What does the weird e mean in math? It’s the Greek capital letter Σ sigma. Roughly equivalent to our ‘S’. It stands for ‘sum’. Read this for starters. Why does E exist in math? The number e is one of the most important numbers in mathematics. … It is often called Euler’s number after Leonhard Euler (pronounced “Oiler”). e is an irrational number (it cannot be written as a simple fraction). e is the base of the Natural Logarithms (invented by John Napier). What is E to zero? Value of e to power zero is e is equal to 1. What is E used for in math? The number e is a mathematical constant approximately equal to 2.71828 and is the base of the natural logarithm, that is the unique number whose natural logarithm equals one. It is the limit of (1 + 1/n)n as n approaches infinity, an expression that arises in the study of compound interest. What is the value of E Power 0? Any number raised to zero is one. Zero is neither positive nor negative so the minus sign before it is redundant. e is constant quantity(roughly equal to 2.71) and when raised to the power 0 it results in 1 as the answer. How do you read E numbers? On a calculator display, E (or e) stands for exponent of 10, and it’s always followed by another number, which is the value of the exponent. For example, a calculator would show the number 25 trillion as either 2.5E13 or 2.5e13. In other words, E (or e) is a short form for scientific notation. Why is e so special? What’s so special about the number e? … ex has the remarkable property that the derivative doesn’t change it, so at every point on its graph the value of ex is also the slope of ex at that point. Can e ever be 0? Since the base, which is the irrational number e = 2.718 (rounded to 3 decimal places), is a positive real number, i.e., e is greater than zero, then the range of f, y = f(x) = e^x, is the set of all POSITIVE (emphasis, mine) real numbers; therefore, e^x can never equal zero (0) even though as x approaches negative … What is E to the infinity power? When e is raised to power infinity,it means e is increasing at a very high rate and hence it is tending towards a very large number and hence we say that e raised to the power infinity is infinity. What does the E mean in an exponential equation? This leaflet provides information about this important constant, and the related exponential function. The exponential constant. The exponential constant is an important mathematical constant and is given the symbol e. Its value is approximately 2.718.

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CC-MAIN-2020-34

http://www.global-sci.org/ijnam/readabs.php?vol=5&no=2&doc=286&year=2008&ppage=302

math

A uniformly optimal-order error estimate of an ELLAM scheme for unsteady-state advection-diffusion equations Kaixin Wang 11 School of Mathematics and System Sciences, Shandong University, Jinan, Shandong 250100, China Received by the editors March 31, 2007 We prove an optimal-order error estimate in a weighted energy norm for the Eulerian-Lagrangian localized adjoint method (ELLAM) for unsteadystate advection-diffusion equations with general inflow and outflow boundary conditions. It is well known that these problems admit dynamic fronts with interior and boundary layers. The estimate holds uniformly with respect to the vanishing diffusion coefficient. AMS subject classifications: 35R35, 49J40, 60G40 Key words: characteristic methods; Eulerian-Lagrangian methods; interpolation of spaces; uniform error estimates

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CC-MAIN-2013-48

https://mathshistory.st-andrews.ac.uk/Biographies/Sleszynski/

math

Ivan Vladislavovich Śleszyński Lysianka, Cherkasy Oblast, Ukraine BiographyIvan Śleszyński's first name is sometimes written as 'Jan', which is the Polish version, while his last name is either given by the Polish 'Śleszyński' or the Russian versions 'Sleshinskii' or 'Sleshinsky'. Although Ivan was born in the Ukraine, he was ethnically Polish, being born into a Polish family living in Lysianka, a town about 160 km due south of Kiev. He studied mathematics at Odessa University and graduated from there in 1875. He then travelled to Germany where he studied under Karl Weierstrass at the University of Berlin, receiving his doctorate in 1882. Returning to Odessa, he became professor of mathematics at the University, holding the position from 1883 to 1909. The year 1909 was significant in another way, for it was the one in which he published his translation of Louis Couturat's famous book The algebra of logic. This work by Śleszyński was more than a translation since it contained Śleszyński's own very useful commentary. This text had a major influence on the development of mathematical logic in Russia since it became the main textbook used by students of the subject over many years. Śleszyński left Odessa and went to Poland in 1911 where he was appointed as an extraordinary professor at the Jagellonian University of Kraków. We should note that in fact Kraków was at this time in the Austro-Hungarian Empire but, remembering Śleszyński's Polish background, it is fair to say that he was moving to Poland. In 1919 he was promoted from extraordinary professor to become the full Professor of Logic and Mathematics the Jagellonian University. He continued to teach at Kraków until, having reached the age of seventy, he retired in 1924. In fact we note that the university decided not to fill his chair after he retired. Śleszyński's main work was on continued fractions, least squares and axiomatic proof theory based on mathematical logic. In a paper of 1892, based on his doctoral dissertation, he examined Cauchy's version of the Central Limit Theorem using characteristic function methods, and made several significant improvements and corrections. Because of the work, he is recognised as giving the first rigorous proof of a restricted form of the Central Limit Theorem. In 1898 Alfred Pringsheim proved that the condition ,ensures the convergence of the continued fraction , where and are complex numbers; a result now known as the Pringsheim criterion. W J Thron states in that this result was established ten years earlier by Śleszyński. Thron demonstrates that Pringsheim was aware of Śleszyński's work, though Pringsheim himself claims that he only became aware of Śleszyński after his article was completed. Six papers by Śleszyński on continued fractions are discussed in where a complete bibliography of Śleszyński's mathematical papers is given. His work on continued fractions is also discussed in . In Bednarowski discusses Śleszyński's book O Logice Tradycyjnej Ⓣ published in Kraków in 1921:- Śleszyński assumes that the part of traditional logic created by Aristotle is a theory of relations which may hold between two classes. He then askes the following question. Having two non-empty classes A and B, what are the possible relations between them so far as having elements in common is concerned? His answer is that between A and B there holds one and only one of five relations which he symbolises by a, b, g, d, e.Śleszyński then represents the five different situations by using Venn diagrams. In the two classes and coincide, in the class is properly contained in , in the class is properly contained in , in the classes , and intersect are all non-empty, and in the final case and are disjoint. Śleszyński then argues as follows. First he says that either and have common elements or they do not. If they do not then we have the situation . Next Śleszyński looks at the situation where common elements exist. Either one of or contains an element not in the other, or they do not. If they do not, then we have the situation . There remains the case where either one of or contains an element not in the other. If fails to contain an element not in we have . Otherwise contains an element not in . If also contains an element not in then otherwise . Śleszyński also goes on to consider what happens when empty classes are allowed and shows that three further relations occur. We should mention another interesting work by Śleszyński, namely On the significance of logic for mathematics (Polish) published in 1923. However, despite the interesting publications we have mentioned, Śleszyński did not publish much of his work. This was rectified by a major two-volume publication in the years following his retirement. One of Śleszyński's most famous students at the Jagellonian University of Kraków was Stanisław Zaremba. In 1925 Zaremba, acting as editor, published the first of two volumes of The theory of proof based on Śleszyński's lectures at Kraków. A second volume appeared in 1929. McCall writes in :- Much indeed can be learned from the rich collection of [Śleszyński's] papers on various subjects in the realm of formal logic, and of mathematical logic and its history ... Introduction to mathematical logic, complete proof, mathematical proof, exposition of the theory of propositions, the Boolean calculus, Grassmann's logic, Schröder's algebra, Poretsky's seven laws, Peano's doctrine, Burali-Forti's doctrine - these are some of the themes pursued in this work, from which I personally have learned a great deal and thanks to which I have got a clear idea of many an unclear thing.We end this brief biography by giving the following quote by Śleszyński:- The point of civilization is the exchange of ideas. And where is this exchange, if everybody writes and nobody reads? - S McCall, Polish Logic, 1920-1939: Papers by Ajdukiewicz Andothers (Oxford University Press US, 1967). - W Bednarowski, Hamilton's Quantification of the Predicate, Proc. Aristotelian Soc. 56 (1955-1956), 217-240. - J J Jadacki, Jan Sleszy'nski (Polish), Wiadom. Mat. 34 (1998), 83-97. - S N Kiro, I V Slesinskii's papers in the theory of continued fractions (Russian) in Continued fractions and their applications 106, Inst. Mat., Akad. Nauk Ukrain. SSR (Kiev, 1976), 61-62. - E Seneta, Jan Sleszy'nski as a probabilist (Polish), Wiadom. Mat. 34 (1998), 99-104. - W J Thron, Should the Pringsheim criterion be renamed the Sleszynski criterion?, Comm. Anal. Theory Contin. Fractions 1 (1992), 13-20. Additional Resources (show) Other websites about Ivan Śleszyński: Written by J J O'Connor and E F Robertson Last Update April 2009 Last Update April 2009

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https://journalofinequalitiesandapplications.springeropen.com/articles/10.1155/2010/363012

math

- Research Article - Open Access -Duality Theorems for Convex Semidefinite Optimization Problems with Conic Constraints © G.M. Lee and J.H. Lee 2010 - Received: 30 October 2009 - Accepted: 10 December 2009 - Published: 12 January 2010 A convex semidefinite optimization problem with a conic constraint is considered. We formulate a Wolfe-type dual problem for the problem for its -approximate solutions, and then we prove -weak duality theorem and -strong duality theorem which hold between the problem and its Wolfe type dual problem. Moreover, we give an example illustrating the duality theorems. - Approximate Solution - Feasible Solution - Convex Function - Linear Matrix Inequality - Constraint Qualification Convex semidefinite optimization problem is to optimize an objective convex function over a linear matrix inequality. When the objective function is linear and the corresponding matrices are diagonal, this problem becomes a linear optimization problem. For convex semidefinite optimization problem, Lagrangean duality without constraint qualification [1, 2], complete dual characterization conditions of solutions [1, 3, 4], saddle point theorems , and characterizations of optimal solution sets [6, 7] have been investigated. Recently, Jeyakumar and Glover gave -optimality conditions for convex optimization problems, which hold without any constraint qualification. Yokoyama and Shiraishi gave a special case of convex optimization problem which satisfies -optimality conditions. Kim and Lee proved sequential -saddle point theorems and -duality theorems for convex semidefinite optimization problems which have not conic constraints. The purpose of this paper is to extend the -duality theorems by Kim and Lee to convex semidefinite optimization problems with conic constraints. We formulate a Wolfe type dual problem for the problem for its -approximate solutions, and then prove -weak duality theorem and -strong duality theorem for the problem and its Wolfe type dual problem, which hold under a weakened constraint qualification. Moreover, we give an example illustrating the duality theorems. Consider the following convex semidefinite optimization problem: where is a convex function, is a closed convex cone of , and for , where is the space of real symmetric matrices. The space is partially ordered by the L wner order, that is, for if and only if is positive semidefinite. The inner product in is defined by , where is the trace operation. for any Clearly, is the feasible set of SDP. Let be a convex function. where is the scalar product on . If is sublinear (i.e., convex and positively homogeneous of degree one), then , for all . If , , , then . It is worth nothing that if is sublinear, then Moreover, if is sublinear and if , , and , then Let be a closed convex set in and . (1)Let . Then is called the normal cone to at . (2)Let . Let . Then is called the -normal set to at . (3)When is a closed convex cone in , we denoted by and called the negative dual cone of . Proposition 2.7 (see ). Following the proof of Lemma in , we can prove the following lemma. Now we give -duality theorems for SDP. Using Lemma 2.8, we can obtain the following lemma which is useful in proving our -strong duality theorems for SDP. for any . ( ) Suppose that there exists such that for any Thus , for any . Hence is an -approximate solution of SDP. Now we formulate the dual problem SDD of SDP as follows: We prove -weak and -strong duality theorems which hold between SDP and SDD. Theorem 3.2 ( -weak duality). Theorem 3.3 ( -strong duality). is closed. If is an -approximate solution of SDP, then there exists such that is a -approximate solution of SDD. for any . Letting in (3.14), . Since and , . Thus from (3.14), Thus is a 2 -approximate solution to SDD. Now we characterize the -normal set to . From Proposition 3.4, we can calculate . Let and Then following hold. (i)If , then (ii)If and , then (iii)If and , then Now we give an example illustrating our -duality theorems. that is, -weak duality holds. Let be an -approximate solution of SDP. Then and . So, we can easily check that . Since , from (3.29), for any . So is an -approximate solution of SDD. Hence -strong duality holds. This work was supported by the Korea Science and Engineering Foundation (KOSEF) NRL Program grant funded by the Korean government (MEST)(no. R0A-2008-000-20010-0). - Jeyakumar V, Dinh N: Avoiding duality gaps in convex semidefinite programming without Slater's condition. In Applied Mathematics Report. University of New South Wales, Sydney, Australia; 2004.Google Scholar - Ramana MV, Tunçel L, Wolkowicz H: Strong duality for semidefinite programming. SIAM Journal on Optimization 1997, 7(3):641–662. 10.1137/S1052623495288350MathSciNetView ArticleMATHGoogle Scholar - Jeyakumar V, Lee GM, Dinh N: New sequential Lagrange multiplier conditions characterizing optimality without constraint qualification for convex programs. SIAM Journal on Optimization 2003, 14(2):534–547. 10.1137/S1052623402417699MathSciNetView ArticleMATHGoogle Scholar - Jeyakumar V, Nealon MJ: Complete dual characterizations of optimality for convex semidefinite programming. In Constructive, Experimental, and Nonlinear Analysis (Limoges, 1999), CMS Conference Proceedings. Volume 27. American Mathematical Society, Providence, RI, USA; 2000:165–173.Google Scholar - Dinh N, Jeyakumar V, Lee GM: Sequential Lagrangian conditions for convex programs with applications to semidefinite programming. Journal of Optimization Theory and Applications 2005, 125(1):85–112. 10.1007/s10957-004-1712-8MathSciNetView ArticleMATHGoogle Scholar - Jeyakumar V, Lee GM, Dinh N: Lagrange multiplier conditions characterizing the optimal solution sets of cone-constrained convex programs. Journal of Optimization Theory and Applications 2004, 123(1):83–103.MathSciNetView ArticleMATHGoogle Scholar - Jeyakumar V, Lee GM, Dinh N: Characterizations of solution sets of convex vector minimization problems. European Journal of Operational Research 2006, 174(3):1380–1395. 10.1016/j.ejor.2005.05.007MathSciNetView ArticleMATHGoogle Scholar - Govil MG, Mehra A: -optimality for multiobjective programming on a Banach space. European Journal of Operational Research 2004, 157(1):106–112. 10.1016/S0377-2217(03)00206-6MathSciNetView ArticleMATHGoogle Scholar - Gutiérrez C, Jiménez B, Novo V: Multiplier rules and saddle-point theorems for Helbig's approximate solutions in convex Pareto problems. Journal of Global Optimization 2005, 32(3):367–383. 10.1007/s10898-004-5904-4MathSciNetView ArticleMATHGoogle Scholar - Hamel A: An -lagrange multiplier rule for a mathematical programming problem on Banach spaces. Optimization 2001, 49(1–2):137–149. 10.1080/02331930108844524MathSciNetView ArticleMATHGoogle Scholar - Jeyakumar V, Glover BM: Characterizing global optimality for DC optimization problems under convex inequality constraints. Journal of Global Optimization 1996, 8(2):171–187. 10.1007/BF00138691MathSciNetView ArticleMATHGoogle Scholar - Kim GS, Lee GM: On -approximate solutions for convex semidefinite optimization problems. Taiwanese Journal of Mathematics 2007, 11(3):765–784.MathSciNetMATHGoogle Scholar - Liu JC: -duality theorem of nondifferentiable nonconvex multiobjective programming. Journal of Optimization Theory and Applications 1991, 69(1):153–167. 10.1007/BF00940466MathSciNetView ArticleMATHGoogle Scholar - Liu JC: -Pareto optimality for nondifferentiable multiobjective programming via penalty function. Journal of Mathematical Analysis and Applications 1996, 198(1):248–261. 10.1006/jmaa.1996.0080MathSciNetView ArticleMATHGoogle Scholar - Strodiot J-J, Nguyen VH, Heukemes N: -optimal solutions in nondifferentiable convex programming and some related questions. Mathematical Programming 1983, 25(3):307–328. 10.1007/BF02594782MathSciNetView ArticleMATHGoogle Scholar - Yokoyama K, Shiraishi S: An -optimal condition for convex programming problems without Slater's constraint qualifications. preprintGoogle Scholar - Hiriart-Urruty JB, Lemarechal C: Convex Analysis and Minimization Algorithms. I. Fundamentals, Grundlehren der mathematischen Wissenschaften. Volume 305. Springer, Berlin, Germany; 1993.View ArticleGoogle Scholar - Hiriart-Urruty JB, Lemarechal C: Convex Analysis and Minimization Algorithms. II. Advanced Theory and Bundle Methods, Grundlehren der mathematischen Wissenschaften. Volume 306. Springer, Berlin, Germany; 1993.Google Scholar This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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http://finance.answers.com/Q/What_questions_can%27t_be_answered_on_WikiAnswers

math

What questions can't be answered on WikiAnswers? Questions that do not have enough information are questions on Wikianswers that are most likely not to get answered. 20 people found this useful Every question and answer at WikiAnswers is contributed to by regular visitors like you. It's all co-operative. We depend on you to ask questions, and we also depend on you to help answer other people's questions. Most questions will get a reply from a nice person, supervisor, expert, or regular use…r who can at least point you in the right direction, if not give you a definitive answer. All WikiAnswers questions are asked and answered by visitors just like you. It is highly unlikely that all the questions here will ever be answered right away since: . Thousands of new questions are asked every day. . Some questions are virtually unanswerable. Yes. Some questions on WikiAnswers get answered. This one just did. A tip for getting your question answered is to make sure that it is in the correct category, and the question is grammatically correct. Of the four questions (including this one) you posted - two were answered fairly quickly. The question 'What is permanetly froaen subsoil called' - contained two spelling errors which you should have corrected before you submitted it. Your final question (this one) has obviously now been answered ! You must remember this is not a live website - it's a forum . You need to be patient to wait for someone to log-on and actually read your question before they can answer it ! (MORE) If the questions you're looking at have been answered by other contributors, then you should see them on the same page as the question. They'll appear in the middle of the page. If the question hasn't been answered, you will see a graphic stating that no one has answered the question yet -- maybe yo…u can assist someone by answering it if you know the answer. (MORE) That's a tough one. Some questions are more difficult to answer than others. For instance, "how do I break up with my boyfriend?" There are a lot of those and they may sit around longer before they are answered. However, who was the third president of the United States is an easier one because it's …objective. WikiAnswers has more answered questions than unanswered ones, but new questions and answers are being added every few minutes so the numbers are never static.. To give it some quantitative sense, according to the conference call by Answer's management on August 13, 2007, out of the total 670,000 questions 375,000 were answered. It gives a slightly better ratio that two to one. (MORE) There are a number of places - depending on what the fundraising is for. There is a Fundraising section under the Politics heading, in 'Business Plans', and also in 'Entertainments and Arts' The questions on WikiAnswers are answered by online citizens on a voluntary basis. They answer the questions that they want to, when they want to. And although there are a number of people that look through the unanswered questions for the purpose of answering them, there are a lot of unanswered que…stions that exist and new ones being asked on a continual basis. Also the proper placement into the category that is closest to the question can have some effect. If a question is in the wrong category perhaps it is not visited as much as it would be if it were in the right category. And then there is always a chance that a person may ask a question that most users do not have the answer to.. (MORE) No, The answers are people like you that want to spend their time to help give as correct as possible answers. So that means that you can answer questions also. Actually, there are some bots answering, but the majority of the answers come from real people. They are not always simple to us and many don't even make sense at all. We have to interpret the question as best we can understand it. Also some people are sophisticated and others are not. Well we do.... Mostly and a lot of the time. But sometimes we don't understand the question, and sometimes we don't get to it because there are so many questions and so little time in a day to research and provide good answers. And then, sometimes, somebody will answer a question when that person (a…hem) really shouldn't be allowed access to a keyboard and by answering the question (even wrongly) it drops off the high priority list and we just don't see it.. If you are not happy with an answer then please, rephrase the question and ask again. We try. We really, really try to provide good, solid information to reasonable questions.. Smile... Life is too short to frown all day..... ;-). And another thing..... We don't get paid for this, you know. If the question is, well, plain ridiculous then nobody bothers to answer. 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Time zones between areas or countries may be as few as 15 minutesapart or as many as 120 minutes apart. Memphis, TN, USA is NOT thesame as Memphis, Egypt. Be specific: Help us to help you! (MORE) WikiAnswers cannot answer many types of questions. Here are some questions that cannot be answered, and will be dropped from the site: . Chatting - questions like "What are you doing?" and "What is the homework?" cannot be answered because this is not a chat room. . Vague Questions - questions t…hat are too vague, like "What is the meaning of life?" or "Why?" cannot be answered. . Incomplete questions - sentence fragments, or partial questions, cannot be understood enough to be answered. (MORE) Everyone! Anyone can share their knowledge or ask questions onWikiAnswers. That's what makes it a WIKI. If you know the answer toan unanswered question, you can share it. If you see an answer thatyou can expand on, you can edit it. If you see an answer that'sjust flat-out incorrect, you can update i…t. 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And thenthere are the supervisors that watch over particular topics andthose that roam around many topics that will spend some timeanswering questions. Answers to questions asked here are theproduct of a large community effort. All answers on WikiAnswers are given by voluntary contributors.Nobody has to answer anything unless they want to give up their ownfree time to do so. They always make a personal choice to give ananswer and then what to say. When they answer a question, theyusually try to give as much information as they think is relevantto the actual question asked. You will have a much better chance ofgetting an early answer to your question if you place it into theright Category! Unless you do that, your question may not beanswered for a long time because it won't be seen by contributorswho know about the subject of the question. If it was placed into the wrong Category your question would haveto wait until a Supervisor finds it and moves it to an appropriateCategory where it will be seen by the someone who may wish tocontribute an answer. People who are members here and others as well. People from allover the world. Anyone who visits can post or edit any answer. Generally, however,questions are edited by those users that feel comfortable with thesubject matter. (MORE) You go to your watchlist and find the question you asked and see if some one made a change. Questions with no value on Wikianswers are questions that are notneeded to be asked and simply waste time and space on this website. If you think you have a good question that ends up here when youask it, E-mail Wikianswers directly and they'll take care of it. if you watch the question wiki answers sends you an email which gives you the link to your questions so you can see the answer You also have your Watchlist which not only records your actions but records for your viewing ability, what others are doing with your questions. Such as someone entering… an answer to your watched question or editing one of your watched questions. (MORE) Quite often! There is a better chance of getting an answer if the question is in correct sentence form. Slang and made up words in the question do not usually get answered.. If you want your question answered, you must post a good question, with all correct spellings, and make sure it makes sense, …plus categorize it correctly. (MORE) Some of the users at WikiAnswers are professionals in their area, and some are not. When you ask a question, everyone has the opportunity to review and answer. its not just one person that answers the questions, any member of wikianswers can answer them if they know the answer. Anyone who answers questions here can stop at any time. After one thousand, after one hundred, or after one answer, any Contributor can opt out.. Or, ironically, No. Many, many questions have not been answered. I couldn't possibly list them all, but they are easy to find if you use advanced search and search only for unanswered questions. Sometimes questions aren't answered because the question is really hard to answer and requires expertise that few people h…ave. Sometimes questions aren't answered because the question itself doesn't seem to make sense. In either case, feel free to jump in and help us out. Your expertise is needed, whether it is how to fix a car, or how to make a question grammatically correct. (MORE) Wiki doesn't answer questions.. We do; based on research and knowledge. There could be many reasons why your question did not get answered, but on average; Wiki gets 1 question asked for every second of every day of the year... so if no one spots your question, it doesn't get answered. Simple as rea…lly. Things that will improve your chances of answers: . putting your question in the right category so that people who can answer are more likely to see. . Not asking homework questions, the rules are there for a reason. . Spelling your question correctly. . Making sure your question is only about one thing, and couldn't be taken in another way. (MORE) There are several criteria that are required to give an evaluation of a bill (banknote): The denomination, the country of origin, the year of printing, and the condition are important. If the bill was issued in the United States, it's also important to note whether it has a small "series letter" …next to or right under the date, and what color ink is used for the bill's seal and serial number. If one or more of these criteria is missing an evaluation is not going to be very accurate. It's also helpful to make sure you have read the bill's type correctly. Up till 1966 U.S. bills were often printed in different varieties. These can be identified by the legend at the top of the bill's front; e.g. "Silver Certificate", "U.S. Note", "Federal Reserve Note", and so on. Finally it is always insufficient to ask for a bill's value based on its serial number. The criteria listed above are far more useful. A serial number is just a counter and it is very difficult, if not sometimes impossible, to link back to a bill's date of issue. . Note to supervisors: This is a category catch-all question.. It should remain protected at all times. . Neither it nor its alternate wordings should be edited or removed. . See related questions for more info about catch-all questions. (MORE) Type the question you want in the enter your question here box and click Go. 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On each answer page - there are two pieces of information. One that tells you the name of the first person to post an answer - and one that states the name of the last person to edit the answer. WikiAnswers does have a lot of answers to questions... but a lot of questions are also unanswered. One thing to try is to ask your question in a little bit different way. Often, there is an already-answered question with a wording that is a little bit different. We try to merge those questions toget…her so that people get answers, but it is a big job, and we are never caught up. (MORE) A lot of them are answered. Put them into the right category andthat will help. There is a general category that you will find:Categories > Hobbies & Collectibles > Coins and PaperMoney. It is good for such questions. Within it are some categoriesfor coins of particular countries. If your question r…elates to oneof those, ask it in the appropriate category. A lot of them are answered. 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There is a general category that you will find:Categories > Hobbies & Collectibles > Coins and PaperMoney. It is good for such questions. Within it are some categoriesfor coins of particular countries. If your question relates to oneof those, ask it in the appropriate category. A lot of them are answered. Put them into the right category andthat will help. There is a general category that you will find:Categories > Hobbies & Collectibles > Coins and PaperMoney. It is good for such questions. Within it are some categoriesfor coins of particular countries. If your question relates to oneof those, ask it in the appropriate category. (MORE) Why can't I edit a question on WikiAnswers and why is the supervisor's name over the answer instead of the answerer? Please contact us (link in Related Links) with the specific linkyou're referring to, so that we can take a look and answer yourquestion! For one thing, it is usually a lot of fun. 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CC-MAIN-2018-51

http://dopapercbby.californiapublicrecords.us/statistics-and-uncertainity-lab-report.html

math

Statistics and uncertainity lab report The meaning of uncertainty statements in laboratory reports previous knowledge of statistical metrology on the part of the reader and involves no mathe. Visual physics laboratory, texas a&m university, college station, tx 77843 there will always be some error or uncertainty present report for that quantity is represented by the average of the measurements statistical analysis shows that about 683% of them will fall within the interval between. Reporting measurements and experimental results statistics is required to get a more sophisticated estimate of the uncertainty the new experiment will be less than one standard error away from the average value from this experiment. These e-lab tools allow you to construct numerical examples to understand the stigler s, the history of statistics: the measurement of uncertainty before 1900, business statistics provides justifiable answers to the following concerns for. This paper takes a broad, pragmatic view of statistical inference to include all aspects of as in laboratory-based experiments, is not possible proxy, or it is disturbing that many research papers report tests only if they yield 'significant. Experiment 3a measurement of resistance – statistical error measurement uncertainty in the period of the pendulum b in lab the in your lab report experiment 3b: measuring potential difference with a digital. Procedures for each lab can be accessed via your lab schedule or in the experiments section please report all problems/breakages immediately don't try. Uncertainty quantification (uq) is the science of quantitative characterization and reduction of aleatoric uncertainty: aleatoric uncertainty is also known as statistical uncertainty, and is inverse uncertainty quantification estimates the discrepancy between the experiment and the technical report tqe 2, 2nd ed , sec. Contrary to what you may have been taught in other classes, we do not want a separate “error analysis” section in your lab report discussion of uncertainties. Creating awareness for the importance of measurement uncertainty is the rely on reports that contain quantitative data from measurement results product quality, experiment results, financial decisions, and medical he specializes in uncertainty analysis, industrial statistics, and process optimization. Statistical (random) error: the statistical uncertainty of a measurement is the the error you report should be calculated from the errors of the time and length. When scientists talk about uncertainty it's not an admission of (and a whole constellation of related concepts in probability and statistics) one of the first truly great precision measurements was henry cavendish's experiment to print website feedback news tip report corrections reprints &. Statistical methods need not always be used to estimate the uncertainty of 17025 related to the estimation of uncertainty of measurement and reporting of the measurement and specifies the form of presentation of results, the laboratory is. Not all lab reports in ib chemistry will be “formal” lab reports, and not all your procedure also should be appropriate to the level of uncertainty needed statistical work also needs to be explained with words to convey understanding of the. 74 finding the uncertainty in calculations from measurements range from the proper and useful keeping of a lab book to statistical methods in finding the see your instructor for actual published reports in physics journals so you can. Statistics and uncertainity lab report Many experiments require measurement of uncertainty statistics very large values of standard deviation can mean the experiment is faulty - either there. Measurement uncertainty assessment (d) in some cases, measurement (even with a small uncertainty) will not resolve and report results with associated expanded laboratory r esu using t-statistics to verify uncertainty budgets2. The usefulness of weighted means statistics as a consensus mean estimator in collaborative studies is lab with the smallest reported uncertainty dominates the data from all other he reports results of an early numerical. - To calculate the uncertainty of your measurements you can report results and standard uncertainty for all results as a whole, or for each result within a set of data is only applicable for cases with normal (gaussian, bell-shaped) statistics. - 3) refine that experiment (how will we estimate uncertainty and compare with 5) briefly define accuracy vs precision and statistics report using the lab. Answer to this pre-lab examines the use of statistics in data analysis 1 math / statistics and probability / statistics and probability questions and answers in the standard deviation σ, which is related to the uncertainty in the measurement. Scientific uncertainty is a quantitative measurement of variability in the data statistical techniques allow us to estimate and report the error surrounding a value quantify statistical error within an experiment and identify systematic error in. Lab e1: statistics of radioactive decay 6/8/06 goals: 1) to learn about the 3) to learn how to report the best value of a measured quantity and its uncertainty. Is a revised and expanded version of the statistics and uncertainty for ipmvp ( evo m&v reports often limit uncertainty discussions to random error ( especially brian ball, phd – national renewable energy laboratory.

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https://www.coursehero.com/file/194542/Quiz2S/

math

Name____SOLUTIONS_______ Physics 125: Analytical Physics II Quiz 2/20/08 The picture shows the cross-section of a thick spherical shell, with outer radius 12.0cmb=and inner radius 6.0cma=. The insulating material of the shell carries a uniform charge density of 332.0μC / mρ=. Use Gauss’ Law to determine a formula for the electric field strength at a distance rfrom the center, where arb<<. Your answer should be a function of r, but all parameters in the function should be numerically evaluated. Choose a Gaussian surface: a sphere of radius r(has the same symmetry as the charge, and passes through the point where we want to know the field). Apply Gauss’ Law: 0encEqεΦ=Left-hand side: By symmetry, everywhere on the Gaussian surface, the E-field has constant magnitude and is perpendicular to the surface (parallel to dAG). Thus, as always for spherical symmetry, 24ErrAEr Eπ=Right-hand side: The volume of the object (vertical lines in this picture) that is This is the end of the preview. access the rest of the document.

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CC-MAIN-2018-05

https://1billionbooks.com/how-to-do-degree-symbol-on-mac/hoin/

math

How To Do Degree Symbol On Mac. First of all, move your cursor on the place where you want to insert the degree character; Option + shift + 8 produces one similar to this 85 ° temperature symbol. The first and the quickest way to type degree symbol on mac is using a degree symbol keyboard shortcut. You keep the option ⌥ and shift ⇧ key pressed, then you type in the number 8, then you finally release everything, which will bring up the degree symbol: In the edit option, you will find the special characters section in the menu bar. Make the symbol degree on mac / macbook : You can get the celsius and fahrenheit degrees symbol in the special characters menu. Option ⌥ + shift ⇧ + 8 = ° the technique: How to insert degree symbol on mac. You keep the option ⌥ and shift ⇧ key pressed, then you type in the number 8, then you finally release everything, which will bring up the degree symbol: If you want to access the symbol, you will need to bring the cursor where you want to insert the symbol and then go to the edit option. The option key is a modifier key (alt) present on apple keyboards. Put your cursor where you want to insert the degree symbol. Go to edit > emoji & symbols or press control+command+space shortcut combination. The first and the quickest way to type degree symbol on mac is using a degree symbol keyboard shortcut. This is one of the methods you can use to type degree symbol on mac. In that case, just use the emoji keyboard (character viewer) to pop in the degree symbol. Typing degree symbols on mac. Know of any other ways to get the degree symbol to appear on a mac or iphone? These key combinations are universal and supported wherever you can insert in mac os x, no matter which app you are on the mac. You can insert a degree symbol (among many other symbols) by using the special characters menu, which is now called the emoji & symbols menu in more recent versions of macos, including macos mojave. Press and hold the alt key and type 0176 on your keyboard. Option + k a symbol type like this degree symbol 54˚. Option+shift+8 produces one like this: You can easily insert or use keyboard shortcuts to ty.

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https://www.ciol.com/iit-roorkee-invites-applications-free-online-course-advanced-engineering-mathematics-via-nptel/

math

IIT Roorkee has organised the Advanced Engineering Mathematics free online course while keeping in mind the usage of mathematics in engineering. The application of Advanced Mathematics in diverse fields of Engineering and Sciences such as Signal processing, Potential theory, Bending of beams etc is unparalleled. This course introduces the students to the various mathematical principles involved in the design and use of engineering principles. Who can enrol in the free online course? This is an Undergraduate level course intended for UG-PG students in the Engineering stream. But anyone can enrol in the course. The only prerequisite is that you also should have the desire to expand the horizon of your knowledge. Moreover, this course is a must-take as Mathematics is so fundamental and common in all engineering courses. Timeline of the course This Elective course has a duration of 12 weeks. It will start on 26 Jul 2021 and end on 15 October 2021. If you want the certificate, you have to give a proctored exam on 24 October 2021. The last date to enrol is 02 August 2021. Who will teach this Advanced Engineering Mathematics course? The instructor Dr P N Agarwal, a Professor in the Department of Mathematics, IIT Roorkee currently supervises 8 PhD students. His area of research includes approximation Theory and Complex Analysis. He has also supervised nine PhD theses and published more than 187 research papers. For NPTEL, Dr Agarwal has delivered 13 video lectures on Engineering Mathematics. He has also completed the online certification course “Mathematical methods and its applications” jointly with Dr SK Gupta. (Same Department) What will the course teach? This is a 12-week-long course. According to the course itinerary and IIT Roorkee, the course contains Analytic Functions, applications to the problems of potential flow, Harmonic functions, Harmonic conjugates, Milne’s method, Complex integration, sequences and series, uniform convergence, power series, Hadamard’s formula for the radius of convergence, Taylor and Laurent series, zeros and poles of a function, meromorphic function, the residue at a singularity, Residue theorem, the argument principle and Rouche’s theorem, contour integration and its applications to evaluation of a real integral, integration through a branch cut, conformal mapping, application to potential theory, review of unilateral and bilateral Z-transforms and their properties. The course will also shed light on the application of the calculus of residues for the inversion formula of Z- transforms and Laplace transforms, review of Fourier integrals and Fourier transforms, Finite Fourier transforms, discrete Fourier transforms and applications, basic concepts of probability, Bayes theorem, probability networks, discrete and continuous probability distribution, joint distribution, correlation coefficient, applications to problems of reliability, queueing theory, service time for a customer in a facility and life testing, testing of hypotheses. How to obtain a certificate from IIT Roorkee? The course is free to enrol and learn. But if you want a certificate, you have to register and write the optional proctored exam. The fee for this exam is ₹ 1000. Also, the successful completion of the exam does not guarantee a certificate. To get a certificate, you need to get 25% from the assignments and 75% of the proctored certification exam score out of 100. Final score = Average assignment score (>10/25) + Exam score (>30/75). If one of the 2 criteria is not met, you will still not get the certificate even if the Final score > 40/100. This printable certificate will carry the stamp from both NPTEL and IIT Roorkee. Further, you can enrol in the free online course here.

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http://www.jiskha.com/display.cgi?id=1321926422

math

the kinetic energy of moving body ids directly praportional to its mass and the square of its speed.if the mass of a bullet is halved by what factor must its speed be increased to have the same kinetic energy as before? Math - Steve, Tuesday, November 22, 2011 at 5:41am E = k * m * v^2 If we halve the mass, now we have E' = k * m/2 * v^2 = E/2 In order to get E' = E, we need a new velocity, v' E' = k * m/2 * v'^2 and we see that v'^2 must be 2v^2 so, v' = v√2

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https://www.phil.cmu.edu/projects/apros/index.php?%20page=overview&subpage=references

math

L & P automated proof search Wilfried Sieg, Richard Scheines. Search for Proofs (in Sentential Logic). Philosophy and the Computer (L. Burkholder, editor), 137-159, 1992 Richard Scheines, Wilfried Sieg. Computer Environments for Proof Construction. Interactive Learning environments Vol. 4 Issue (2), 159-169, 1994. Wilfried Sieg, John Byrnes. Normal Natural Deduction Proofs (in classical logic) . Studia Logica 60, 67-106, 1998. Wilfried Sieg, Saverio Cittadini. Normal Natural Deduction Proofs (in Non-classical logics) . Mechanizing Mathematical Reasoning, LNAI 2605, 169-191, 2005. Wilfried Sieg, Clinton Field. Automated search for Gödel's proofs. Deduction, computation, experiment (R. Lupacchini and G. Corsi, eds.), Springer-Verlag, 2008, 117-140. (The paper was originally published in the Annals of Pure and Applied Logic 133, 2005, 319-338) AProS Project: Strategic Thinking & Computational Logic. Logic Journal of the IGPL 15 (4), 2007, 359-368 W. Sieg, On mind & Turing's machines; Natural Computing 6, 2007, 187-205 W. Sieg, Searching for proofs (and uncovering capacities of the mathematical mind); to appear C.D. Schunn and M. Patchan, An evaluation of accelerated learning in the CMU Open Learning Initiative course Logic & Proofs; Report, Learning Research and Development Center, University of Pittsburgh, May 31, 2009

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https://library.curriki.org/oer/Worksheet--Gas-Laws-1/?mrid=43186-43421-49401-44432-43422

math

1) A sample of gas occupies 8.00 liters at STP. What will be its volume at 273 K and 1200.0 mm Hg? 2) What volume will 200.0 mL of gas at 327ºC occupy if it is cooled to 27.0ºC under constant pressure? 3) A sample of gas occupies 275 mL at 52.0ºC and 720.0 mm Hg. What will be its volume at 77.0ºC and 788 mm Hg? 4) What volume is occupied by 0.250 g of O2 at 25.0ºC and 155.500 kPa? 5) What is the molecular mass of a gas if 1.55g of the gas occupies 560. mL at 27.0ºC and 2.25 atm? 6) A 250. mL sample of oxygen is collected over water at 25.0ºC and 760.0 mm Hg pressure. What is the pressure of the dry gas alone? 7) A 32.0 mL sample of hydrogen is collected over water at 20.0ºC and 750.0 mm Hg. What is the volume of the dry gas at STP? 8) Given the reaction: KClO3(s) -> KCl(s) + O2(g) How many grams of KClO3 are required to produce 30.0 liters of O2 at 27.0ºC and 745 mm Hg? 9) Given the reaction: Al(s) + HCl(aq) -> AlCl3(aq) + H2(g) If 0.755g of Al react with an excess of HCl, how many liters of H2 will be produced at 22.0ºC and 0.988 atm? 10) How many grams of copper are required to produce 225 mL of NO collected by displacement of water at 29.0ºC and 748 mm Hg? 3Cu(s) + 8HNO3(aq) -> 3Cu(NO3)2(aq) + 2NO(g) + 4H2O(l) 11) A liquid was analyzed to be 54.5%C, 9.10%H, and 36.4%O. An empty flask, whose mass was 45.32g, when filled with the vapor of the liquid at 735 mm Hg and 99.2ºC had a mass of 46.05g. The volume of the flask was found to be 263.2 mL. What is the empirical and molecular formula of the compound? 12) The density of an unknown gas at 20.0ºC and 749 mm Hg is 1.31 g/liter. Calculate its molecular mass.

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CC-MAIN-2022-40

http://www.demonstrations.wolfram.com/SagnacInterferometer/

math

This Demonstration simulates the operation of a Sagnac interferometer. The interference between the two output beams depends on the placement of the two mirrors. THINGS TO TRY For more details about the Sagnac interferometer, please refer to the Wikipedia entry for " Wolfram Demonstrations Project Published: May 14, 2013 Embed Interactive Demonstration More details » Download Demonstration as CDF » Download Author Code » More by Author Sagnac Interferometer with Three Mirrors Michelson Interferometer and Haidinger Fringes Rotating Michelson-Morley Interferometer Michelson Interferometer with Equally Spaced Fringes Mach-Zehnder Interferometer with Phase Shifts Fabry-Pérot Interferometer and Rings Tracing Rays Reflected from a Spherical Mirror Ordinary and Extraordinary Refractive Indices in a 2D Anisotropic Crystal Blue Sky and Red Sunset S. M. Blinder Browse all topics The #1 tool for creating Demonstrations and anything technical. Explore anything with the first computational knowledge engine. The web's most extensive Course Assistant Apps » An app for every course— right in the palm of your hand. Wolfram Blog » Read our views on math, science, and technology. Computable Document Format » The format that makes Demonstrations (and any information) easy to share and STEM Initiative » Programs & resources for educators, schools & students. Join the initiative for modernizing Step-by-Step Solutions » Walk through homework problems one step at a time, with hints to help along the way. Wolfram Problem Generator » Unlimited random practice problems and answers with built-in step-by-step solutions. Practice online or make a printable study sheet. Wolfram Language » Knowledge-based programming for everyone. Note: Your message & contact information may be shared with the author of any specific Demonstration for which you give feedback. © 2018 Wolfram Demonstrations Project & Contributors | Note: To run this Demonstration you need Mathematica 7+ or the free Mathematica Player 7EX Download or upgrade to Mathematica Player 7EX I already have

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http://supercgis.com/relative-error/relative-error-practice.html

math

A landscaping team has been asked to reseed the side lawn at a local university. To the nearest inch, the length of the blackboard is 42 inches, and its width to the nearest inch is 34 inches. Then computer the volume. Oz, the cat, weighs 15 pounds to the nearest pound. this contact form A temperature reading is taken to be 9 degrees below zero Fahrenheit, to the nearest degree. The groundskeeper is replacing the turf on a football field. What, to the nearest percent, is the percent of error in the measurement of the radius? a.) Choose: 0.70531112 0.0070037132 0.0070531112 0.70037132 b.) Choose: 0.7% 0.07% 0.1% 7.1% Explanation Part a: The absolute error is 0.05 (half of 0.1). b. A measurement is taken to be 13.6 in. Choose: NOTE: The re-posting of materials (in part or whole) from this site to the Internet is copyright violation and is not considered "fair use" for educators. One-half of 0.1 is 0.05. Solution: Given: The measured value of metal ball xo = 3.14 The true value of ball x = 3.142 Absolute error $\Delta$ x = True value - Measured value = Add and subtract 0.05 to 3.4. Let x represent the %. Relative Error Definition you didn't measure it wrong ... http://mathworld.wolfram.com/RelativeError.html Wolfram Web Resources Mathematica» The #1 tool for creating Demonstrations and anything technical. Absolute And Relative Error In Numerical Methods and Stegun, I.A. (Eds.). Since the smallest of these values is 9.5, use 9.5 to determine the minimum area. http://mathbitsnotebook.com/Algebra1/Units/UNErrorPractice.html Then the relative error is defined by where is the absolute error. The system returned: (22) Invalid argument The remote host or network may be down. What Is Absolute Error Percent error = 0.7053111193% = 0.7% 15. What is the tolerance interval for this measurement? Which interval represents the location of the exact value of d, prior to rounding? The actual radius is 25 inches. http://www.tutorvista.com/physics/formula-for-relative-error A value, d, has been rounded to the nearest tenth andis 5.7 units. Absolute And Relative Error Examples Choose: 1 in 1.5 in 1.9 in 2 in Explanation The lower limit will be 1.7 - 0.2 = 1.5 10. Relative Error Formula Cassidy measures the side of a square and rounds her answer to the nearest integer as 10 inches. What is the student's percent of error on this measurement? weblink Answer 2. The width (w) could be from 5.5m to 6.5m: 5.5 ≤ w < 6.5 The length (l) could be from 7.5m to 8.5m: 7.5 ≤ l < 8.5 The area is b.) What is the percent error, to the nearest tenth of a percent, in calculating the area? Absolute Error Formula and the absolute error is 0.05 in. Please try the request again. Select "Check Answer" to see if your answer is correct; select "Give Up" if you want to see the answer. http://supercgis.com/relative-error/relative-error-vs-relative-uncertainty.html Practice online or make a printable study sheet. Choose: 5.65 < d < 5.75 5.65 < d < 5.75 5.65 < d < 5.75 5.65 < d < 5.74 Explanation Remember that ALL values that round to 5.7 Difference Between Absolute Error And Relative Error A measurement is taken to be 20 ± 0.05 m. when measuring we don't know the actual value! No ... The system returned: (22) Invalid argument The remote host or network may be down. Due to his negligence he takes the value as 50.32 m whereas the actual precise value is 50.324 m. Relative Error Chemistry Solve C = 2(pi)r = 471.24 for r.

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https://www.chegg.com/homework-help/mathxl-tutorials-on-cd-for-elementary-algebra-2nd-edition-chapter-1.3-problem-1q-solution-9780321593146

math

We have to find the set of first four positive, odd numbers. Odd number is an integer which is not a multiple of two. If it is divided by two, the result is a fraction. Odd numbers always end with a digit of 1, 3, 5, 7 or 9. 11, 35, 567367

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CC-MAIN-2019-22

https://www.arxiv-vanity.com/papers/math-ph/0609057/

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Integrable Models From Twisted Half Loop Algebras [4mm] N. Crampé111 and C. A. S. Young222 Department of Mathematics, University of York, Heslington Lane, York YO10 5DD, UK This paper is devoted to the construction of new integrable quantum-mechanical models based on certain subalgebras of the half loop algebra of . Various results about these subalgebras are proven by presenting them in the notation of the St Petersburg school. These results are then used to demonstrate the integrability, and find the symmetries, of two types of physical system: twisted Gaudin magnets, and Calogero-type models of particles on several half-lines meeting at a point. This paper has two motivations. On the one hand, we are interested in physical models of particles on a number of half-lines joined at a central point. Such systems, for free particles, have been treated in, for example, [1, 2]. Here we would like to consider interacting models, to establish that integrable examples of such models exist, and to find their symmetries. We shall work out explicitly two examples: the Gaudin model and the Calogero model . Both have numerous applications in physics and in mathematics. For example, the reduced BCS model for conventionnal superconductivity can be diagonalized in an algebraic way using the Gaudin model. Other, more recent, applications of the Gaudin model in quantum many-body physics can be found for example in the reviews [6, 7]. Besides being of intrinsic interest due to its exact solvability, the Calogero model plays a role in the study of two dimensional Yang-Mills theory , the quantum Hall effect and fractional statistics . Our second motivation is algebraic. The notation of the St Peterburg school is a powerful tool when working with the Yangian of and its subalgebras: the reflection algebras [13, 14] and twisted Yangians . These are quantum algebras, but the construction has a classical limit in which the quantum -matrix and Yang-Baxter Equation are replaced by their classical counterparts (see for example ). The classical limit of the Yangian is the half loop algebra, and the limits of the reflection algebras and twisted Yangian are subalgebras of this half loop algebra defined by automorphisms of order 2. But there also exist, at least in the classical case, other subalgebras of the half loop algebra, defined by automorphisms of higher finite order. We wish to study these subalgebras using classical -matrix techniques. It is well-known that the half-loop algebras associated to Lie algebras are crucial in the study of Gaudin models and Calogero models. These algebras provide, in the former case, a systematic way to construct the model (see e.g ) and, in the latter case, the symmetry algebras of the system [18, 19, 20]. In both cases, they allow one to prove the integrability of the model . We shall find similar connections in the cases studied in this paper. Indeed, we shall see below that the order subalgebras of the half loop algebra appears naturally in the description of models on half-lines. This paper is structured as follows. We begin with a brief review of the half loop algebra of and its subalgebras associated to automorphisms of order . We make use of the notation of the St Petersburg school to find Abelian subalgebras. In the subsequent sections these algebraic results are shown to provide new quantum integrable models and demonstrate their symmetries: section 3 discusses “twisted” Gaudin magnets, and section 4 introduces Calogero-type models on half-lines joined a central point. We end with some conclusions and a short discussion of classical counterparts of these results. 2 Half loop algebra and subalgebras 2.1 St Petersburg notation and half loop algebra The half loop algebra based on is the complex associative unital algebra with the following set of generators , subject to the defining relations for and . It is isomorphic to the algebra of polynomials in an indeterminate with coefficients in , with the generators identified as follows: where are the generators of , satisfying the commutation relations It will simplify our computations to introduce the notation of the St Petersburg school: let be the matrix with a in the th slot and zeros elsewhere. These are the generators of in the fundamental representation. Let us now gather the generators of in the matrix where () and is a formal parameter called the spectral parameter. Note the flip of the indices between and , which will prove convenient later. The algebraic object is an element of , and as usual we refer to as the auxiliary space and as the algebraic space. In what follows we shall require several copies of both spaces. We use letter from the start of the alphabet to refer to copies of the auxiliary space and numerals for copies of the algebraic space. Let us introduce also where is the permutation operator between two auxiliary spaces: the letters and stand respectively for the first and the second spaces. By definition, it satisfies (). The matrix , usually called the classical R-matrix (see for example ), satisfies the classical Yang-Baxter equation and allows us to encode the half loop algebra defining relations (2.1) in the simple equation This form of commutation relations can be obtained easily by taking the classical limit of the presentation of the Yangian of introduced by L.D. Faddeev, N.Yu. Reshetikhin and L.A. Takhtajan of St Petersburg . By taking the trace in the space in (2.7), it is straightforward to show that the coefficients of the series are central. The quotient of the algebra by the relation is isomorphic to the polynomial algebra . The identification (2.2) between the generators of and now reads and is to be understood as the formal series . Note the similarity between relations (2.5) and (2.8): the only differences are that the second auxiliary space (denoted ) in (2.5) is replaced by an algebraic space (denoted ) and that the spectral parameter is shifted by . In fact, there exists a more general solution of the relations (2.7) in the -fold tensor product of , From now on, we work in the enveloping algebra in which, for example, the product makes sense. 2.2 The inner-twisted algebras Let be an inner automorphism of of order . One way to define is by its action on matrices in the fundamental representation: where satisfies ; the action of on the abstract algebra is then given by , or, in the notation of the previous section, The eigenvalues of are the -th roots of unity , and for each the map is the projector onto the -eigenspace: Since , decomposes into the direct sum of eigenspaces of . This decomposition respects the Lie bracket, in the sense that if and then and is said to be a -gradation of . By a change of basis we can take where . Note that the -eigenspace of is the Lie subalgebra . Let us define that is, is the subalgebra of in which each element of degree is also in the -eigenspace of . There is a surjective projection map , defined by . In view of (2.12), this sends which defines the formal series whose expansion contains by construction a complete set of generators of . and has the property that for all The coefficients in the expansion of are central in , as may be seen by taking the trace in space or in (2.20). But there exist also other abelian subalgebras in , as follows. The coefficients in the expansion of are mutually commuting, or equivalently for all values of and . Moreover, they commute with the generators of of degree zero: The algebraic elements in generate . Proof. The details of the proof are given in appendix A. In particular, we recover (for ) the fact that commute and (for ) the results of Hikami concerning the classical limit of the reflection algebra. 2.3 Outer Automorphisms In the previous section, we focused on inner automorphisms. Now, we show how to modify the construction to study outer automorphisms. Modulo inner automorphisms, the only outer automorphism of is generalized transposition, which has order 2. Let be a real invertible matrix satisfying with (for , must be even), and define an outer automorphism by , or equivalently where is matrix transposition in the space . The eigenvalues of are and, as before, the decomposition of into the direct sum of eigenspaces of defines a -gradation. One may introduce the matrices where and the second case is valid only for even. A well-known result in linear algebra is then that is congruent over the reals to , i.e. for some real matrix . From this one sees that the -eigenspace of is the Lie subalgebra for and for . Once more we may now define that is, the subalgebra of in which each element of degree is also in the -eigenspace of . The projection map is , and, given (2.24), this sends which defines the formal series , whose expansion in inverse powers of contains a complete set of generators of . The commutation relations of this subalgebra can be written simply by using the notation with the formal series. where and has the symmetry property that Note that these commutation relations can be obtained from the classical limit of the twisted Yangian introduced in . More abstractly, the relations (2.29) and (2.30) can be regarded as defining an algebra, which can then be seen to be embedded in the half loop algebra according to (2.27). It is well-known that the centre of this subalgebra is generated by the odd coefficients of the series (see for example , section 4). But we have also The quantities in the expansion of are mutually commuting, or equivalently for all values of and . Moreover, The elements in generate for and for . Proof. The details of the proof are given in appendix B. 3 Gaudin models 3.1 The Inner-twisted Gaudin Magnets The quantum Gaudin magnet, introduced in , is an integrable spin chain with long range interactions. The Gaudin Hamiltonians for the model with sites are where are complex numbers. (Recall that permutes the and spins.) This model is usually called the -type Gaudin model. It may be obtained from the more general class of integrable Hamiltonians by specifying that the spin at each site is in the fundamental representation of . Now, given proposition 2.2 above, we can obtain new integrable models, as in the following proposition. These models describe spins placed at fixed positions in the plane, each of which interacts with the central point and with the other spins, not only directly, but also via their images under the rotation group of order . The model described by any one of the Hamiltonians is integrable. This model has symmetry. Proof: From the definition (2.18) of , one finds with as given in the proposition. (The identity for is helpful in showing this.) It then follows from proposition 2.2 that . Since (for ) these operators are independent we have found commuting conserved quantities, completing the proof of integrability of the Hamiltonian . Next, from the relation , also proved in proposition 2.2, we deduce that , which gives the symmetry of the model. For , we obtain the Hamiltonian of the BC-type Gaudin model studied in . If the sites carry the fundamental representation of , our Hamiltonian is Let us remark that in the case () supplementary conserved quantities, called higher Gaudin Hamiltonians, can be found by computing for example (see e.g. ). The question of whether this is possible in the generalized cases () studied here remains open. 3.2 The Outer-twisted Gaudin Magnets Using the algebraic result of proposition 2.4, we can also succeed in constructing integrable models based on outer automorphisms, as follows: The model described by any one of the Hamiltonians is integrable. The model has symmetry (resp. symmetry) for (resp. ). with given as in the proposition. Then, we deduce from proposition 2.4 that , and since the operators are independent for different , this proves the integrability of . The symmetry algebra is deduced from proved in the proposition 2.4. Every choice of representation for the sites then yields a Gaudin-type model. (It is worth remarking that it is possible to choose different representations at different sites.) For example, in the fundamental representation of , the Hamiltonian is We may interpret as a Gaudin model with boundary as in the BC type model (equation (3.6), and see also ). The term in (3.8) corresponds to the interaction between the spin represented in and the ‘reflected’ spin transforming in the contragredient representation. This type of boundary is called soliton non-preserving and has been implemented in other integrable models [23, 24, 25, 26]. The final term in (3.8) corresponds to the interaction between particles and the boundary. 4 Calogero Models We turn now to the second class of integrable system of interest in this work, the Calogero models. We seek to construct dynamical models of multiple particles on a star graph, whose pairwise interactions are determined by a potential of the usual Calogero type, namely , where is the linear distance separating the particles in the plane of the star graph. We will first construct models of particles of unspecified statistics; subsequently, by specifying statistics and parity, we arrive at Calogero models for particles with internal spins. 4.1 The case Let us first recall the Calogero model based on the root system , and in particular the use of Dunkl operators in demonstrating its integrability . Consider a quantum mechanical system of particles on the real line. Let be the position operator of the particle, and write the position-space wave function as Let be the operator which transposes the positions of particles and , Let us denote the permutation group of elements and the transposition of the elements and . Each element can be written in terms of transpositions, namely . Then, we can define as the shorthand for the product (even though the expression of in terms of transpositions is not unique, is well-defined due to the commutation relations satisfied by ). The sign of , denoted , is the number of these transpositions modulo 2. It follows from the relations that the Dunkl operators commute with one another, and consequently that the quantities form a commuting set also. The are algebraically independent for , and these give commuting conserved quantities of the model with Hamiltonian which is therefore, by construction, integrable. The next step is to consider particles with internal degrees of freedom, which we take to be in the fundamental representation of . The wave funtion becomes where . As we define operators which transpose the positions, we introduce operator which transposes the spins We define similarly to the matrix for acting on the spins. As explained before, to use the St Petersburg notation, we need supplementary spaces called auxiliary spaces (which are and, in this case, isomorphic to the quantum space) and denoted by the letters , ,… The conserved quantities (4.5) then emerge in a natural way from the matrix because (as one can see using ) Here (4.9) is nothing but a modified version of the monodromy matrix (2.10). The parameters are replaced by the Dunkl operators, and since the quantum spaces are chosen to be in the fundamental representation, becomes the transposition operator (for ). Now because the commute with each other and with all operations on the internal degrees of freedom, obeys the half loop algebra relations (2.7) exactly as before. Suppose, finally, that the particles are in fact indistinguishable, which is often the case of real physical interest. One must then impose definite exchange statistics on the wavefunction: where for bosons and for fermions. The projector onto such states is The following relation demonstrated in is crucial, because it implies that the modified generators preserve the condition , and obey the same algebraic relations as the original . From we may define , and hence . Using , one obtains that the are once more commuting conserved quantities of the system with Hamiltonian where we are now able to replace , which acts on particle positions, by , which acts only on the internal degrees of freedom. Moreover, since commutes with , the model has a half loop symmetry algebra. The subtlety in all this is that the Dunkl operators themselves do not obey any relation analogous to (4.13). There are thus essentially three steps in this procedure to construct an integrable Hamiltonian for a system of indistinguishable particles: Find commuting Dunkl operators, and hence Construct the appropriate projector onto physical states, Prove the relation . 4.2 Dunkl Operators for the order inner-twisted case We can now turn to applying these ideas to the model of interest in the present work. We consider a system of particles living on half-lines – “branches” – joined at a central node, as in figure 1. The branches are given parametrically by , , and we shall denote them by As before, let be the position operator of th particle. (Note that the spectrum of is not real, but only for the superficial reason that we choose to regard the half-lines as subsets of the complex plane.) In addition to the , which exchange particle positions, we can define now new operators which move the particles between branches: It is useful to collect together the algebraic relations satisfied by the , , and : with all the rest commuting. To construct an integrable model, the first task is to find a suitable generalization of the commuting Dunkl operators introduced above. The Dunkl operators defined by for arbitrary parameters , commute amongst themselves: Consider first the terms at order . We have using the relations (4.19) and the definition , which together imply . The two terms of this type occurring in are which cancel, after a change of the summation index in the second. The two terms containing cancel similarly. The terms occurring at order are of the form These vanish trivially unless at least one of the indices matches at least one of . It is straightforward, though tedious, to check that the terms with exactly one index in common sum to zero, by using the relations (4.19) to bring every such term into e.g. the form and then summing the fractions directly. The terms in which both indices match give and here the sum over may be re-written as which then vanishes by shifting the dummy index in the second and fourth terms. The terms involving may be treated similarly. These Dunkl operators have been introduced previously in as Dunkl operators associated to complex reflection groups. A proof of their commutativity is already given but is based on different computations. As in the case above, the quantities are then mutually commuting, forming a hierarchy of Hamiltonians of an integrable system. Their detailed forms are rather complicated – for example, in the case of branches with only particles and , we find that the first three are

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http://insider.espn.go.com/nba/insider/columns/story?columnist=sheridan_chris&id=2701751

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Not so Stern: Commish lets Isiah off the hook GARDEN FIGHT FALLOUT • Hill: Don't blame 'thugs' for fight • Bucher: Melo walking dangerous line again • Sheridan: Not so Stern penalty for Thomas • Stein: Answering brawl questions • Stein Blog: Way too easy on Isiah • Sheridan: NBA to use experience to rule • Stein Blog: Nuggets' Iverson plan • Melo won't appeal, will serve suspension • Northwest pulls mag featuring Anthony • Karl calls Isiah 'a jerk' • League looking into roles of Isiah, players • Carmelo Anthony apologizes • Notable brawls in NBA history • Knicks' loss to Nuggets turns into free-for-all • Allen Houston not surprised by penalties. • Dan Patrick Show: Union president Billy Hunter discusses punishments. • Karl blasts Isiah • Daily Dish: Sheridan, Ford discuss brawl • Reggie Miller: Isiah and Karl deserve suspensions • Stephen A. Smith's take • Karl says Isiah's actions 'despicable' • Isiah issued warning before brawl • Players fight at Madison Square Garden • Sheridan analyzes brawl • Stephen A. breaks down brawl • Isiah Thomas discusses battle • Nuggets react to situation • Kiki Vandeweghe's take • What do you think of the punishment? MORE NBA HEADLINES - Adidas Men's New York Knicks Amar'e Stoudemire #1 Road Royal Replica Jersey

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https://vrs.amsi.org.au/student-profile/jia-jia-qian/

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An enduring object of study of the field of geometric analysis is the relationship between the local and global properties of a shape. For example, if we seek to minimise the area of a surface bounding a given volume (a global property), is the boundary always a given by surface of constant positive curvature (a local property)? This is known as the isoperimetric problem, and has been studied for many centuries. The global property is often expressed as either an integral constraint, or else minimisation of an energy. This gives rise to local properties, often in the form of a differential equation that must be satisfied. The simplest of such geometric shapes is a closed curve in the plane. Remarkably, planar curves are still a rich field of study, despite their long history. One recent result is the fourvertex theorem. This states that the curvature of a closed curve must have four extremal points. The converse to this was only discovered in 1998, by Dahlberg. Another example is the knotting of curves: is there a local or global property that will detect whether a curve is knotted? Jia Jia is a third-year undergraduate student studying maths and computer science student at Monash University. She is interested in graph theory and analysis, and hopes to explore many more areas of mathematics.

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https://cmm.cit.nih.gov/intro_simulation/node8.html

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We now delve into electrostatics to estimate the electrostatic polarization free energy, , involved in the transfer of a solute with an arbitrary charge distribution from vacuum to aqueous solution. is the interaction between the charge distribution and its reaction potential, the potential induced by the charge distribution in the presence of the dielectric boundary at the solute-solvent interface. First, we review some basics. Again, we will focus on important results, and leave most of the mathematical details to textbooks . Don't worry if the equations are unfamiliar; just stay tuned for the punch line. All problems in electrostatics boil down to the solution of a single equation, Poisson's equation: Let's examine two model systems, a point charge and a point dipole, each immersed in a dielectric medium. In the following two boundary-value problems, we simply state the answer, giving as a function of position for all points in space. In these problems, we seek in regions were there is no charge (). Thus, we need solutions to the special case of Poisson's equation known as Laplace's equation, , that satisfy two boundary conditions. First, must be a continuous function, e.g., at the dielectric boundary. Second, because there is no `free' charge (charge other than the induced polarization charges) at the dielectric boundary, the normal component of the electric displacement, , will also be continuous at this boundary. First, we model a single ion in solution as a sphere of radius a with a point charge q at its center, immersed in a solvent of dielectric constant . Aside from the point charge at the center, there is nothing inside the solvent-exclusion cavity, and so the dielectric constant inside is the permittivity of free space . The spherical symmetry of this system renders it a problem of only one dimension, the distance r from the point charge. The solution is: One step up in complexity from a point charge is a point dipole. So let's replace the point charge at the center of our solvent-exclusion sphere with a point dipole . With this model system we can approximate the solvation energy of a neutral molecule possessing a permanent dipole moment. Again, the dielectric constant of the solvent is , and the dielectric constant inside the spherical molecule is . This cylindrically symmetric system has two independent dimensions, the distance r and the angle from the direction of the dipole vector. We get : Note that in equations 6 and 7 the potential inside the spherical molecule is a sum of two terms. In each case, the first term is the potential that would exist in the absence of the dielectric boundary at , and the second term is the potential induced in the spherical cavity by the charge distribution's interaction with the dielectric (e.g., the solvent). The energy of the charge distribution arising from this second term (the reaction potential) gives the electrostatic contribution to the solvation free energy. The energy of a point charge in its reaction potential is one half of the product of the charge and the reaction potential. The `one half' appears because this is not the energy of a charge in an external electric field. Here, the charge has contributed to the creation of the field through its electrostatic interactions with the dielectric. So our continuum model of the solvent predicts that the electrostatic polarization free energy of solvating a spherical ion is The energy of a dipole in its reaction field (the negative gradient of the reaction potential) is minus one half of the dot product of the dipole and the reaction field. Again, this is half the energy of a dipole in an external electric field. The reaction field of the dipole is parallel to the dipole, and we get Note that both G values are zero if , i.e., if we haven't changed the dielectric constant of the environment. Still and coworkers have proposed the following approximate expression for the free energy of solvent polarization for an arbitrary charge distribution of N charges: As shown in the following figure, this GB approximation behaves appropriately in important limiting situations. For N identical, coincident () particles of charge q, it gives the correct Born energy (equation 8, for a single particle of charge ). For two charges of equal and opposite sign, it approaches the dipole result (equation 9) at short separation distances, as it should. For two well separated charges ( ), it approaches the appropriate energy: the two Born energies plus the energetic change in the Coulomb interaction between the two charges due to the dielectric medium. |GB approximation (in red) to solvent polarization energies for two charges of equal radii as a function of separation. The dependence of Born radii on atomic positions is neglected here. Upper curves: Equal and opposite charges with G_dipole (blue) at small separation and Coulomb + Born polarization energies (green) at large separation. Lower curves: Equal charges with G_ion (blue) at zero separation and Coulomb + Born polarization energies (green) at large separation.|

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http://library-business.com/2018/09/

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http://www.chegg.com/homework-help/questions-and-answers/capacitor-constructed-concentric-conducting-cylindricalshells-radius-inner-cylindrical-she-q635178

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A capacitor is constructed of two concentric conducting cylindrical shells. 0 pts endedThis question is closed. No points were awarded. A capacitor is constructed of two concentric conducting cylindricalshells. The radius of the inner cylindrical shell is 2.10 10-3 m, and that of the outer shell is2.27 10-3 m. When the cylinders carry equal andopposite charges of magnitude 1.8310-10 C, the electric field between theplates has an average magnitude of 4.65104 V/m and is directed radially outwardfrom the inner shell to the outer shell. (a) Determine the magnitude of the potentialdifference between the cylindrical shells. (b) Determine the capacitance of this capacitor.

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https://www.allmathwords.org/en/a/arc.html

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Pronunciation: /ɑɹk/ Explain |Figure 1: Arcs on a Circle|| An arc is any smooth curve joining two This article will focus on arcs of An arc of a circle is sometimes called a circular arc. Any two points on a circle define two arcs. If the two points are on a of the circle, each arc is called a semicircle. If the two points are not on a diameter of a circle, they define two arcs. The larger arc is called the major arc, and the smaller arc is called the Adjacent arcs are two arcs that share an endpoint. Arcs are measured based on what portion of a whole circle they occupy. A whole circle measures 360° or 'rad' is an abbreviation for radians. An arc occupying 1/2 of a circle would then measure 360° / 2 = 180° or 2π rad / 2 = π rad. Click on the blue points and drag them to change the figure.| What is the arc length of a arc of a circle with circumference 4 that covers 90 degrees? |Manipulative 1 - Arc Length Created with GeoGebra.|| Arc length is defined as the linear length of an arc. For arcs of circles, the arc length is calculated as a portion of the total circumference of a circle. if the arc measures 72°, and the circumference is the arc length is 72°/360° · 22cm = 4.4cm. - McAdams, David E.. All Math Words Dictionary, arc. 2nd Classroom edition 20150108-4799968. pg 18. Life is a Story Problem LLC. January 8, 2015. Buy the book - Arc length. www.khanacademy.org. Kahn Academy. 6/19/2018. https://www.khanacademy.org/math/geometry/hs-geo-circles/hs-geo-arc-length-deg/e/circles_and_arcs. Cite this article as: McAdams, David E. Arc. 4/11/2019. All Math Words Encyclopedia. Life is a Story Problem LLC. https://www.allmathwords.org/en/a/arc.html. 4/11/2019: Changed equations and expressions to new format. (McAdams, David E.) 12/21/2018: Reviewed and corrected IPA pronunication. (McAdams, David E.) 6/14/2018: Removed broken links, changed Geogebra links to work with Geogebra 5, updated license, implemented new markup. (McAdams, David E.) 3/2/2010: Added sentence on adjacent arcs. (McAdams, David E.) 1/2/2010: Added "References". (McAdams, David E.) 11/12/2009: Added arc length. (McAdams, David E.) 6/11/2008: Added paragraph on the measure of an arc. (McAdams, David E.) 6/7/2008: Corrected spelling. (McAdams, David E.) 4/18/2008: Initial version. (McAdams, David E.)

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https://inderjtaneja.com/2020/10/07/geometrical-numerical-and-symmetrical-representations-for-the-days-of-2020/

math

In this work, the days of year 2020 are represented in two different ways. One way is numerical, and another way is geometrical. In numerical representations, four different forms are considered. The first one is of crazy type, and the second one is of power type. In these two cases the year ends in 20. The third one is representations in terms of single letter “a”. This is done only for the months of April and August. The forth numerical representation is of factorial type. In this case, four different ways are considered. One ending in 20, and other three ending in 2020. For these representations, we used the idea of 5!, 6! and 8!. The geometrical representation is new, and is not done so far. In this case the representations are for the year ending in 2020. This we have done for each day separately. The first 364 days are organized within a square of 9×9. The last two days of year, i.e., 30.12.2020 and 31.12.2020 are organized in a square of 11×11. All the geometrical representations are organized in symmetrical way. In this situation five types of symmetries are defined, such as, color design symmetry, design symmetry, half-design symmetry, half-color half-design symmetry and half-color design symmetry. All these symmetries are based on well known reflection symmetry. By no means, we can say that these representations are unique. There are much more possibilities. The whole work can be downloaded at: - Inder J. Taneja. Geometrical, Numerical, and Symmetrical Representations for the Days of 2020. Zenodo, October 04, 2020, pp. 1-201, http://doi.org/10.5281/zenodo.4065069 - Months of 2020: - Color Design Symmery: These are of double reflection symmetry in colors and in design and are of equal patterns. Complete work with more examples of different kinds of symmetries and numerical representations can be seen in a paper cited above for download. 30 thoughts on “Geometrical, Numerical, and Symmetrical Representations for the Days of 2020”

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