Wikipedia:Reference desk/Archives/Mathematics/August 2011

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August 1

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 1

1. Aleph and beth numbers
2. An inequality

August 2

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 2

1. Sum formula

August 3

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 3

1. Statistical significance concept
2. BZ2 question about entropy
3. Epsilon
4. a question of modal logic, validity and rules of inference

August 4

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 4

1. Estimating flow in partially filled pipe

August 5

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 5

1. A good calculator for Mac OS X
2. 653xy divisible by 80
3. A Simple PDE

August 6

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 6

1. Parabolic Problem
2. Differentiability
3. Imaginary Numbers

August 7

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 7

1. How natural and universal is mathematics?

August 8

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 8

1. I need a resource for studying the basics of convexity and relations
2. Categorical description of a nonstandard model of first order Peano arithmetic?

August 9

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 9

1. Uniform vs Pointwise Continuity
2. Is the book's answer wrong?
3. Dirverging in all Directions
4. Some Basic Numerics Questions
5. Limit as x approaches 0 cos(x)/x

August 10

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 10

1. Question about Time and Complexity Class RE
2. Is zero really an even number?
3. Shape similarity?
4. Statistics – p and α

August 11

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 11

1. Length of a golf shot
2. Directions in study
3. physics
4. math class

August 12

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 12

1. Can this be solved / approximated tractably?
2. musical notes

August 13

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 13

1. Infinite Dimensional Spaces
2. Metamath question
3. what if everyone on facebook friended their friends' friends and they had to accept
4. Is Yahoo answers correct?
5. Monotone functions

August 14

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 14

1. Imaginary Fibonacci

August 15

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 15

1. "Most"
2. factoring integers
3. Is the probability of guessing the right number out of N choices one in N^2?
4. Riemann?

August 16

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 16

1. Extracting parameters from a matrix form ellipse

August 17

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 17

1. Air Resistance Terminal Velocity
2. DeeperQA's nearly the last theorem
3. Real Number
4. Self study mathematics
5. Quadratic equation with a mod operator
6. knapsack problem problem

August 19

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 19

1. Binomial theorem and convergence

August 20

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 20

1. Recursive sequence
2. Subsets
3. Statistical hypothesis testing of Poisson processes
4. (1+x)^n ≥ 1+nx
5. Ratio from percent
6. derivative
7. ? (what is infinity times zero?)

August 21

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 21

1. Arithmetic mean of two numbers > Geometric mean of two numbers.
2. Circle geometry
3. Triangles
4. range of a transformation on the set of polynomials
5. Number Triangle
6. math (pressing homework question)

August 22

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 22

1. Simplify a sum involving binomial coefficients
2. Trajectories, gravity, acceleration, straightforward calculus
3. Getting a Formula Given Points: Step-Like Function
4. Derivation of Poiseuille's Law

August 23

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 23

1. Multiplying a Factorial by Another Factorial
2. Factorization
3. Why the long tail is just a 2 variables graph and not a 3 variables graph??

August 24

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 24

1. Real cube roots of the identity matrix
2. Problem from Spivak's Calculus

August 25

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 25

1. Logarithmic Spiral
2. Proof too easy?

August 26

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 26

1. Limit to infinity
2. FLAW in Cauchy's proof for the inequality of arithmetic and geometric means?!
3. Cumulative position probabilities as a result of tossing dice
4. I have a question about fractals.

August 27

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 27

1. Show that the set of bounded functions is infinite dimensional
2. Previous problem with generalized dice
3. Can you solve this?
4. Commas in non-decimal numbers

August 28

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 28

1. Kernel of a transformation on the set of polynomials
2. Partial Derivative of Volume of Cone
3. Cone terminology
4. Romanian math
5. A question about $zeta(0)$

August 30

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 30

1. Expected sum of random variables

August 31

Wikipedia:Reference_desk/Archives/Mathematics/2011 August 31

1. When is xxxx0831 prime?
2. Solving a problem with constraints
3. Sum of n-sums
4. is it correct
5. Difference quotient