Wikipedia:Reference desk/Archives/Mathematics/January 2010

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January 1

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 1

1. Maths - discovered or invented?

January 2

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 2

1. Original Basic Discovery or No?
2. How to factorise
3. Geometric algebra question - involutions
4. Proof of continuity
5. What's a mathematical coincidence?

January 3

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 3

1. Generalized Heat Equation
2. Diffusion Equation
3. Formal sums for quotients of primorials

January 4

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 4

1. conversions
2. Cantor's Ordinal Numbers
3. Term by Term Integration of a Fourier Series
4. Sums of squares
5. Rates of decline
6. jection

January 5

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 5

1. Convergence
2. Question on combinations
3. Möbius Maps
4. NP and NPC

January 6

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 6

1. Predicting number of items in a set (statistics)
2. division by zero
3. Quotients and products of topological spaces.
4. Limits
5. Extension fields
6. How to solve for B
7. Logarithms and order of operations

January 7

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 7

1. TI 84 plus calculator program

January 8

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 8

1. Simple Mathematics, Requiring Data
2. Differentiable?
3. Number of partitions of a set in classes of given cardinalities.
4. Letter grid problem
5. Limits

January 9

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 9

1. Arrow's impossibility theorem and real elections
2. 1001 (number)
3. Pairwise coprime integers
4. calculating pi
5. Standard deviation of 4 numbers

January 10

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 10

1. Sum
2. Harmonic series

January 11

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 11

1. Perimeter of a trapezium
2. Smoothness Scale In Number Theory

January 12

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 12

1. Normal Closures Qual. Exam
2. solution of differential equation of motion of a quarter car
3. Locally invertible function from R^2 to R
4. Estimating number ratios

January 13

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 13

1. Cube root function on the space Mn of matrices
2. finding the centre of a circle
3. Nilpotent homomorphisms
4. 35 degrees east

January 14

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 14

1. An elementary homotopy equivalence
2. Consecutive integers with same sum of proper divisors

January 15

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 15

1. Is there a name for this property of sets?
2. Is a set that contains only itself hereditary?
3. Continuity of power functions
4. Infinite ordinals
5. Properties of certain symmetric matricies?

January 17

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 17

1. Archimidean Spiral Segment
2. Identity Matrix Multiplication
3. Weird summation notation
4. Certain repeating digits

January 18

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 18

1. Asians
2. differential
3. What does this symbol/suffix mean?

January 19

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 19

1. Policy recommendation for comparing citation totals or h-index for any mathematician
2. Variation on equals sign
3. P.G.F. question
4. 3 rotations about the vertices of a triangle: identity map

January 20

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 20

1. Eigenvalues and eigenvectors
2. Riemann integral
3. A few more geometry problems!
4. Geometry question

January 21

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 21

1. Riemannian geometry
2. Fractional chromatic number
3. Expected value problem
4. can you explain turbo codes OR LDPC?

January 22

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 22

1. Weaker versions of Fermat's Last Theorem
2. Bounds

January 23

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 23

1. Finding a surface on which integrals of multiple functions are 0

January 24

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 24

1. Query on an online document - subgroups of A5
2. College question: What material do I need to have a firm grasp on?
3. Factoring Polynomials
4. Complex icosidodecahedrons

January 25

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 25

1. Cryptography
2. Differential equation
3. Topological Group Question

January 26

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 26

1. Inverse Trigonometric Identity Prove
2. Cross ratio equal to 1/2tan^2 of spherical distnce
3. I was wondering...
4. Normed Spaces
5. A loxodromoid?

January 27

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 27

1. Calculating the area of a triangle while on a coordinate system
2. Effective procedure
3. Three little geometry puzzles
4. sequence space
5. Smooth structures (manifolds)
6. Another triangle problem
7. How to build an ellipse?

January 28

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 28

1. Golden Ratio
2. Reversion to the mean
3. NP definition
4. j-invariant

January 29

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 29

1. Why is the perimeter of a spherical triangle less than 2 pi?
2. Unique bid auctions
3. Cardinality
4. ratio inequality
5. What algorithm?
6. Proof
7. Derivative question
8. Monty hall paradox

January 30

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 30

1. percentages,round offs and number based systerms
2. could there be ANY change made in the rules of logic without immediate inconsistency?
3. Hexadecimal

January 31

Wikipedia:Reference_desk/Archives/Mathematics/2010 January 31

1. Normal vectors
2. Rhombicosidodecahedron
3. Strange use of log
4. Function harmonic on a strip
5. Intersecting cylinders
6. What is the link between the edges, faces and vertices of a 3D shape?