Wikipedia:Reference desk/Archives/Mathematics/December 2009

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December 1

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 1

1. Exponential or Super-Exponential Growth In A Novel Sequence
2. negative exponent dividend
3. steps and results of simplification
4. Transpose
5. Cyclic hexagon
6. $mathbb{Z}_{n}[x]$ in GAP

December 2

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 2

1. Sets and the absolute infinite
2. A strange puzzle
3. Absolute Levi-Civita

December 3

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 3

1. If a^b = a^c, then b = c.
2. Growth of Log and Power

December 4

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 4

1. Same Question As Three Days Ago, But In The Other Direction
2. Quick Q about $e^{ipi}+1=0,,!$
3. minima help please
4. Naive or automatic forecasting from multivariate time-series
5. Infinite roots
6. Borel sets
7. Paper folding

December 5

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 5

1. optimisation tric??
2. Probability of object being owned by person
3. Speed calculation

December 6

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 6

1. A Related Problem In Base Four
2. finite differentiation
3. Integral

December 7

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 7

1. random 8 digit number reads the same both ways

December 8

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 8

1. Standard form
2. Geometric argument for area under x²

December 10

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 10

1. sudoku
2. Integral estimate

December 11

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 11

1. weighted mean and errors
2. Non-linear ODE question

December 12

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 12

1. Is This Problem Intractable?
2. Expectation
3. Convergence of the boundary for this series
4. STEP papers
5. A very simple question

December 13

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 13

1. Did the Mayans or Babylonians invent zero first?
2. More on finite differences

December 14

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 14

1. Numbers
2. Cardinal Ordinal
3. Indistinguishable balls in distinguishable boxes

December 15

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 15

1. Isoperimetric yard problem
2. rotated figure
3. Question in computing probabilities
4. Logarithms and Conic Sections.
5. Normal variables, independence, covariance

December 16

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 16

1. Multiply Intrinsically 4-Palindromic Numbers
2. Finite differences of factorials
3. combinatorics (pigenhole etc)
4. Distributivity
5. double-checking statistics
6. items arranged question

December 17

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 17

1. recognition of tangent plane for a function
2. Easiest way to decide if a point is within a polygon?
3. Are the slopes of $f(x)$ and $f^{-1}(x)$ necessarily reciprocal?

December 18

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 18

1. Non-isomorphic digraphs
2. Continuous or not?

December 19

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 19

1. Differentiability of a function from R^2 to R at the origin
2. Distance from a point to a line
3. Plotting a fractal curve defined by binary digits

December 20

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 20

1. hyperbolic tangent derivative
2. Local class field theory
3. New Identity?
4. Rouché's theorem
5. Matrix subgroups

December 21

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 21

1. Calculus History
2. Fréchet Second Derivatives and Taylor Series of matrix functions
3. Vector cosine
4. Calculi(Non Newtonian)
5. Article introducing complex numbers
6. Principles of Mathematics
7. Reducible Polynomials With All But Constant Coefficient Equalling 1
8. googol

December 22

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 22

1. Desperately Seeking a Faster Algorithm
2. Summation of finite differences
3. Stationary Points in Higher Dimensions
4. Symbol for 'such that'
5. Cartoon books about mathematics

December 23

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 23

1. Functional Analysis
2. reduction algorithm
3. 120 links between five people??
4. Why does a*b give the area of a rectangle? / Why does arithmetic give meaningful geometric results?

December 24

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 24

1. Green's second identity and Green's functions for the Laplacian
2. sequence space
3. Rolling sphere

December 25

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 25

1. Easy way of deciding if two lines cross?

December 26

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 26

1. dual spaces of Sobolev spaces
2. Is the word "induce" used technically or non-technically?
3. Does U(1) = SU(1)
4. Linear combination of matrices
5. Algebra over a ring that is a field?

December 27

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 27

1. Algorithm to reduce polynary equations to minimum form
2. Measure Theory & Countability
3. Math and calculations
4. Limit of a sequence
5. Computationally expensive problems
6. The all-ones vector, and how to notate it

December 28

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 28

1. Lebesgue measure versus Borel measure
2. Universal enveloping algebra
3. How to solve math poblems without calculating
4. Sum and Difference of Two Tangents

December 29

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 29

1. Hypervolume of an 8-sphere
2. transcendental functions
3. No math after 12th grade?
4. Symmetries and perturbations

December 30

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 30

1. non polynomial difference
2. Calculate my age as percentage of USA age.
3. Solving for x giving the min
4. 'Reproducing generations problem' or 'sum of 2 to the power n'

December 31

Wikipedia:Reference_desk/Archives/Mathematics/2009 December 31

1. Ryan's hypo-whatsisis?
2. Gauss–Jordan elimination = reduced row echelon form?
3. Some basic topology of the torus
4. Looking for random "shopping" algorithm