Wikipedia:Reference desk/Archives/Mathematics/January 2011

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January 1

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 1

1. Graph Theory

January 2

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 2

1. Countable union of countable sets cannot have cardinality $aleph_{2}$
2. Method of Characteristics

January 3

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 3

1. Percentages and Probability

January 4

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 4

1. statistics
2. Permutations
3. Identifying a quotient

January 5

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 5

1. Special magic squares
2. non-trivial irreducible character of primitive permutation character is faithful?
3. Groups of order 24
4. 1+1=2
5. What constitutes a valid solution?
6. Math and prejudice

January 6

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 6

1. Tetrahedral angles
2. Learning to read and write proofs
3. Websites first postings
4. Remainder term
5. LaTeX

January 7

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 7

1. Differentiation w/ respect to complex conjugate
2. limit
3. Question: what is the meaning of R suerscript n, subscript ++.
4. distance measure
5. What does it mean to raise big-O to a power?
6. Inverse Function Theorem

January 8

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 8

1. Pretty stupid question about statistics
2. Cryptography
3. Group theory: what is precise definition of A: B en A.B ?

January 9

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 9

1. Alternate proof of the Weierstrass approximation theorem

January 10

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 10

1. Godel sentences and the arithmetic hierarchy
2. Groups
3. Earth vs. human vs. rhinovirus

January 11

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 11

1. Squared differences
2. Series and Intergration
3. How to visualize integer sequences?
4. Adding paraboloids

January 12

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 12

1. Maths competition puzzle
2. Weird length issue
3. 1 2 3 4 5 6 7 8 9 = 100
4. cylindrical/spherical integration

January 13

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 13

1. Coit tower
2. Valid operations on cylindrical and spherical vectors
3. Time dilation limit

January 14

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 14

1. Gradients

January 15

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 15

1. Sums of squares of normal random variables with the same distribution
2. Sum of multipliers
3. mathematical realism
4. Reviving an old topic: Ambiguity in Number Theory

January 16

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 16

1. Bases and spans for the space of infinite sequences $ell_{2}$
2. Analytic geometry question
3. Geostationary Satellite coordinate transformation
4. "General Limit Theory"
5. magic machine statistics

January 17

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 17

1. continuous function on C equals zero somewhere
2. math formula to computer formula
3. Logical formula for existence of a path in a graph
4. Is a group uniquely determined by the orders of its elements?
5. How to read aloud the usual notation for the definite integral
6. Probability of doubling up
7. Use of Baire Category Theorem

January 18

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 18

1. Calculating the probability that two binomial distributions are in order
2. "sgn" in Latex
3. Topology - Sequential spaces and sub sequential spaces
4. Math game
5. Mathematics and language
6. Combination of error distributions

January 19

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 19

1. Satisfiability Problem

January 20

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 20

1. Finding limits using first principles
2. Integration of vector-valued functions
3. does this work?

January 21

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 21

1. Vector calculus question

January 22

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 22

1. Fibre Bundles and Actions
2. Limit of a sequence of complex polynomials discontinuous at a single point
3. sine function
4. Filters in Topology
5. Latus rectum of a parabola
6. Polynomial approximation of a non-analytic complex function
7. Latex: texorpdfstring with explicit superscript sign ^ in it
8. Got stuck on a limit problem

January 23

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 23

1. Tournament pairing question
2. Quick question - showing an equation is insoluble (?)
3. Number system that subtracts as well as adds

January 24

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 24

1. z scores on a ti 84 plus
2. Looking for a math word

January 25

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 25

1. Integrable sets of functions
2. Basic probability question
3. Random function on the sphere

January 26

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 26

1. Day of the week
2. Geometrical symbol for midpoint, slope, and length
3. my seperable diff eq general solution does not agree with the book

January 27

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 27

1. Combine Standard Deviations

January 28

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 28

1. Probability
2. pls help
3. The Stone Cech Compactification by Ultrafilters
4. average in a class
5. Learning R

January 29

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 29

1. ZFC and its implications
2. Constructing mathematical models.
3. Ostensibly simple probability question?
4. Taking from a large population without replacement

January 30

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 30

1. First digits of 10^n
2. Arc length proof
3. Converting from rectangular to polar form
4. Explanation of a few topology concents

January 31

Wikipedia:Reference_desk/Archives/Mathematics/2011 January 31

1. Start at different points, add 1. Evaluate evenness.
2. Interchange of summation and differentiation with Fourier series
3. Probabilistic Inclusion Exclusion.