Wikipedia:Reference desk/Archives/Mathematics/October 2009

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October 1

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 1

1. The answer to this system of equations?
2. type 1 and 2 errors of statistical hypothesis testing
3. Limits on discrete sets
4. P value

October 2

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 2

1. Collatz conjecture
2. Theorem
3. Achilles numbers: Never consecutive?
4. Question about shoelaces

October 3

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 3

1. Calculator
2. Calculator (solution)
3. Rectangle under pinhole projection

October 4

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 4

1. Math
2. trigonometry
3. Best way to calculate if a line crosses another line, or a polygon.
4. Powerful numbers

October 5

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 5

1. Odds ratio vs. relative risk
2. dx
3. Constant Morphisms
4. Proving the existence of a function
5. Fourier Series Representation

October 6

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 6

1. Question on topological manifolds
2. Geometry

October 7

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 7

1. Integration by Substitution
2. solving mathematical problems
3. Probability question

October 9

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 9

1. Double check logic on this permutation question

October 10

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 10

1. Linear map
2. Number Theory
3. Do the intuitionists agree that an equation of the form (x − a)(x − b) = 0 has two solutions only?

October 12

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 12

1. Sphere volume and surface area
2. Ring Extension
3. Cardinality
4. Curve fitting
5. Interesting sounds
6. No solutions to equation similar to FLT
7. Markov chain-like model
8. What is a Mexican pyramid?

October 13

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 13

1. Vectors and matrix algebra dot products et al
2. An Almost-Primality Test
3. Vectors in meterology
4. percent comparisons
5. Some probability questions...

October 14

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 14

1. Constructor
2. Polynomial ideals
3. Newton's Method
4. Russell's paradox
5. Lottery: 6 numbers out of 49, expected values in case of large jackpots

October 15

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 15

1. simple formula for fractions in computer code

October 16

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 16

1. cbse mathematics question papers
2. The Limiting Function of a Fourier Series

October 17

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 17

1. Quadratic forms on real matrices
2. Good way to remember meet vs join?
3. Certain conformal map projections

October 18

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 18

1. Getting pi with a limit
2. Application of the PNT to a sequence of numbers
3. Can kite be a trapezium?
4. Smallest number which have the first n positive integers as divisors
5. Modular forms: Finding the fundamental domain for a finite index subgroup
6. Use of abacus in United States education

October 19

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 19

1. Euclidean scaling

October 20

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 20

1. Ergodic splitting in L^p
2. Common Complementary subspaces in finite dimensional vector spaces
3. Word Probability Question
4. homework help plz?
5. 2D splines

October 21

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 21

1. Extension of the Bateman-Horn conjecture to subsets
2. Ostrowski
3. I am really intersted in mathematitics adnd solving questions is one step ahead. However I've always got problems here and there as below
4. QUADRATIC EQUATION
5. History of Mathematical Thought on Base Ten

October 22

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 22

1. Theorem that says that valency maximal distance of distance-regular graph is "very very big"?
2. how many articles should I read?
3. Multiple integral
4. Exponential random variable probability

October 23

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 23

1. Binary trees and transient Markov Chains
2. The Frustrating Integral
3. Peano axiom of induction
4. statistics problem

October 24

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 24

1. Groups of order 112
2. Subset of an intersection
3. Grades formula
4. Equalities of means

October 25

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 25

1. Hierarchical probability model
2. Pyramids
3. Invariant Reliabilty Index (ϐ)

October 26

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 26

1. Logs
2. Diagonalise these 2 QFs at once - must be going wrong somewhere
3. 0.9...
4. Domains wot change

October 27

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 27

1. Is there an Erdős–Ko–Rado theorem for binary codes?
2. Calculating a chord of a sphere
3. Irrational exponents
4. Power set of a Cartesian product
5. BMO-style question (ish) on sums & products
6. Any method for solving the following equation...

October 29

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 29

1. Differential operators of order 4 - help me before I die of boredom
2. Logarithmic differentiation
3. help this formulae identify itself
4. Algebraic long division

October 30

Wikipedia:Reference_desk/Archives/Mathematics/2009 October 30

1. Piping a pump/filter for minimum number of valves
2. probability question
3. Finding global maximum
4. Intervals of real numbers
5. While we're talking about intervals...
6. Degenerate conics
7. Simple geometrical question