Wikipedia:Reference desk/Archives/Mathematics/May 2009

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May 1

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 1

1. Pairing colours, permutations and such
2. Complex integral
3. Exponential Addition

May 2

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 2

1. Derivatives of functions of more than one variable
2. Binomial expansion
3. Essential singularity
4. calculating rate constant k

May 3

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 3

1. How to make my own do it yourelf leading indicator?
2. What's going on here?
3. Adjusting a statistical snapshot for duration
4. Applications of Conway's cosmological theorem

May 4

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 4

1. Application of Differentiation
2. Penney's Game
3. decimal to HEX

May 5

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 5

1. Möbius strip
2. A couple probability questions about points on a sphere
3. Arclength of tan from pi eigths to pi fourths
4. Rational points on a circle

May 6

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 6

1. Limits of differentiable functions
2. Cycloid
3. how to do monte carlo for statistics?
4. Non-discrete valuation ring
5. Group homomorphisms
6. for Buffon's needle does the length of the needle not matter

May 7

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 7

1. Chaitin version of Gödel incompleteness theorem
2. bijection between RXR and R
3. why does having a unique right inverse for some function f imply bijectivity while having a unique left inverse doesn't?
4. List of functional analysis topics
5. statistics: is 98% confidence the same as 98% of cases out a billion?
6. 1 +1 ?
7. trigonometric functions
8. Arcs and Radii
9. Harmony in music based on periodic waveforms
10. Division of exponential random variables
11. Theorem guaranteeing minimum value of bounded function

May 8

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 8

1. A derivative of the log of sigmoidal functions
2. Mathematics - Sequence analysis
3. trigonometric conversions
4. what does statistical confidence MEAN
5. what good are sins and cosins and all that stuff
6. someone above said 98% of cases out of a billion isn't 98% confidence -- why
7. Calculation problem including vector
8. factoring integers in polynomial time
9. Z-hat

May 9

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 9

1. Gradient of linear graph
2. okay, is THIS confidence?
3. Logistic equation vs logistic map
4. MLS Matrix transformation

May 10

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 10

1. Suggestion for a good book on axiomatic set theory
2. Numerical Methods for Solving PDEs
3. Means
4. Top mathematical journals
5. Simple vector equation: most general solution
6. Areas of circles
7. bicycling paradox

May 11

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 11

1. Curvature question
2. do number of consecutive misses of coin toss follow normal distribution? What is the standard deviation?
3. Change of variables in 3 dimensions - please help!

May 12

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 12

1. Countable axiom of choice--is it consistent with Axiom of Determinacy
2. Binary relations and equivalent conditions = Argh

May 13

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 13

1. What are the benefits to humans of using a tree structure?
2. Second difference equation
3. Does mathematics exist in an empty universe?
4. Triangle areas
5. Finding an approximation to a linear system
6. 7 tens

May 14

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 14

1. how many possible soduko variations are there
2. geometry and algebra
3. Limit of sequence
4. Rate of change
5. Totally real fields
6. Question from a mechanics past paper

May 15

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 15

1. shape of solution space
2. logarithm
3. Fatou's Lemma and liminfs
4. Irrationality of Pi

May 16

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 16

1. Correcting linear least squares coefficients for small samples
2. Showing an element is irreducible
3. Proof that n orthogonal vectors form a basis for $\mathbb {R} ^{n}$?

May 17

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 17

1. does anyone know how to solve these?
2. Fairly simple $\nabla$/inequality problem
3. LaTeX fraction spacing

May 18

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 18

1. Decomposition of a symmetric matrix
2. how many spheres diam D1 can pack on the surface of a larger sphere diam D2
3. What is the ratio of the area of a circle to a square
4. 90 Degree Angle

May 19

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 19

1. Lifting prime ideals to integral extensions
2. Name that theorem...
3. Exponential functions multi-valued?

May 20

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 20

1. Goldbach conjecture
2. Parimutuel betting
3. transcendental equation
4. does anyone know how to solve this????

May 21

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 21

1. concentric circles
2. Spheres in an n-dimensional sphere
3. joint probability distribution terminology

May 22

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 22

1. HOW HE DID IT?
2. probability book?
3. Maximum Volume of Cone made from cut sector of a circle.
4. working out foot pound ratio for powder in grams

May 23

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 23

1. A LaTeXnicality
2. Probability of dots on a circumferance

May 24

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 24

1. Margin vs Markup
2. value of pi
3. Nonlinear Homogeneous Differential Equations
4. Plus-or-minus range

May 25

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 25

1. New Elementary Suggestive Results Found By Birthday Coincidences Related To History
2. Proving inequality
3. perfect squares
4. conformal bijective map
5. Finding cube root

May 26

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 26

1. Statistical fallacies in White Nationalist propaganda?
2. Nicer proof of Stirling's approximation
3. Bijection between R and C
4. Novel Problem Related To Research
5. Published puzzle
6. Diffeology
7. Implicit differentiation problem

May 27

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 27

1. Chess openings
2. Notation for derivatives ?
3. Convergence of the series z^(n!)

May 28

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 28

1. Wolfram Alpha exponentiation quirk?
2. Solving for a matrix...

May 29

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 29

1. How many different types of six sided dice are there?
2. Analytical Continuation

May 30

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 30

1. Eulerian city?

May 31

Wikipedia:Reference_desk/Archives/Mathematics/2009 May 31

1. Lottery question
2. Parentheses and functions
3. Mathematical Drawing