Wikipedia:Reference desk/Archives/Mathematics/March 2010

Welcome to the Wikipedia Mathematics Reference Desk Archives
The page you are currently viewing is a monthly archive index. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.

March 1

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 1

1. Critical point of a constant function
2. Sums & products of random numbers.
3. Integers into a Line with an Overlap
4. The spinor map

March 2

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 2

1. Hyperbolic Line Reflection, and Isometry between H/D
2. HOW TO DRAW
3. Riddle, where is the mistake in ALL x = 0 ?
4. Logistic Function
5. Strange proof

March 3

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 3

1. Taylor polynomials and errors (homework)
2. Maximum angle
3. Topology: Is there a name for a function differentiable in its connected open domain?
4. Ring Z[sqrt(2)]: complete set of units
5. Casual language usage, or is there an example?

March 4

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 4

1. Simplifying an expression involving radicals
2. Vectors
3. Small lie brackets and commutators
4. Random walk

March 5

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 5

1. semiprime number theorem
2. Prime numbers
3. Toilet paper calculus
4. Mobius Strip
5. A Simple Linear Functional Equation
6. 400 million French Francs in 1940

March 6

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 6

1. is number theory worth studying if one doesn't plan to make a contribution?
2. Quotient constructions
3. Inner Product Spaces
4. 120 deg?
5. sin-1
6. Expected minimum from non-parametrized distribution
7. How to determine the angle a line drawn between two concentric arcs makes with the tangent of the outer arc..
8. statistics-- median in following case

March 7

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 7

1. How to do a Recurrence plot
2. Simplifying Trig Identities
3. Undefinability by any "almost-pure identity" formula (of first-order):
4. How many different types of phase-space plot are there?
5. Graph of a smooth function is a smooth embedded surface?
6. The probability of a normally distributed random variable being a particular value

March 8

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 8

1. Catching cheaters in a math class
2. Easy free software for drawing (phase space) graphs from statistical time-series data?
3. Calculating eigenvector for beginners

March 9

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 9

1. Homework question
2. Divisibility In Digit-by-Digit Inter-Base Conversion

March 10

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 10

1. How do you prove that $x$ generates the multiplicative group of $GF(p)[x]/f(x)$ if $f(x)$ is a primitive polynomial?
2. Project Euler problem
3. Is C^∞ dense between the measure preserving transformations?
4. 'Extension' of a linear transformation?
5. Complex Analytic Functions

March 11

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 11

1. Quick question on integration by parts and non-integer values of the Gamma function
2. Length of a function
3. Why doesn't Cantor's diagonal argument apply to rationals?
4. What is the 98th percentile in a Normal distribution with μ=100 and σ=15?

March 12

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 12

1. little project
2. How many types of numbers are there?
3. Absolute value of a quaternion
4. Domain of a function
5. Statistical significance when discussing a population
6. feedback rating

March 13

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 13

1. Maclaurin expansion
2. Statistics - Conditioning
3. Stats -- algebraic manipulation of V(X) and E(X), etc.
4. Symmetric linear solve
5. simple question.
6. is there any proof that current compression couldn't be much better?
7. L'Hopital's rule
8. Approximations to roots

March 14

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 14

1. Approximate solutions to equation
2. Geometry problem
3. Terminology: equivalence of ordering or optima
4. Sparse Graph Colorings
5. Integration
6. L'Hopital vs. Landau

March 15

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 15

1. Normal distributed random variable mathematics
2. Representation of Haar scaling function in terms of Haar wavelet
3. Cases where Euclid's first common notion doesn't apply
4. crisis in geometry

March 16

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 16

1. Sum of i?
2. four dimensional space.
3. Was 2 always prime?
4. Request for input at our Entertainment desk
5. Inner Product Spaces
6. X/Y

March 17

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 17

1. Plank Time
2. Local connection between measure preserving transformations
3. Character question
4. Lambert W function for a base other than e

March 18

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 18

1. Integrating differential terms independently of each other in a single equaiton
2. formulas which induce functions
3. Expected value of a difference
4. Distance along a parabola
5. Drive time commute
6. Rank-Nullity

March 19

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 19

1. Fractions
2. "Half" of the real numbers
3. sum of fractional differences
4. Alternative notations for exponentiation
5. Automorphisms of the Riemann sphere
6. q test not for idiots ... (a q test table for a 99.9999% confidence level?)
7. rack

March 20

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 20

1. Integration by substitution
2. Interest computation- when compounding frequency is lesser than pay out frequency
3. Could someone learn all the notation from all the branches of mathematics in a year?
4. Restriction

March 21

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 21

1. Finding the nth term of a sequence given a bunch of terms (statistics question)
2. Arc length extension
3. Probability question
4. how to copy the equations and all mathaematical terms from wikipedia to MS Word?
5. Formula to undistort the image from a shiny sphere

March 22

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 22

1. Statistics question: Estimating a probability distribution given sample trials
2. Iterations of a multiplicative function
3. Inverse functions $e^{x}-e^{-x}$ and $lnleft(frac{x+sqrt{x+4}}{2}right)$
4. If and only if symbol to use in thesis
5. Optimal location of a bridge

March 23

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 23

1. How to parametrise distribution given a few CDF points
2. nth iteration of a koch snowflake
3. what's the best area for contributing something practical
4. Distribution of a subset of a distribution
5. how much do words impede mathematics
6. Questions about Birkhoff Normal form

March 24

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 24

1. How to display surds on the TI-84 Plus
2. the volume of a solid bounded by the lines x=0, y=0, z=0 and the plane x+y+z=9
3. Poincare Conjecture and Ricci flow
4. Beads on a necklace

March 25

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 25

1. Circle
2. A matrix M raised to the i-th power (i being imaginary), or the natural base raised to the M-th power (M being a matrix).
3. Dissections in Riemann Integration
4. Two dimensional representation of an arbitrary distance matrix
5. Normed field
6. Periodic formula of an EKG shape?
7. Reverse engineering a graph
8. Number of non-isomorphic graphs in n vertices?

March 26

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 26

1. unsolved problems
2. Navier-Stokes equation
3. Wiener process properties
4. Opposite Category of Sets
5. Finite differences in exponential powers
6. I need your knowledge in all mathematical realms you are familiar with.
7. Curve Sketching

March 27

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 27

1. Lattice of quotient groups
2. maruschka doll and half-life - fractals?

March 28

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 28

1. How much should my game cost?
2. Tricky trig integral
3. How to tell if a time series is nonlinear or not?
4. Probability

March 29

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 29

1. Rouché's theorem and real solutions
2. Birthday Probabilities

March 30

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 30

1. Guests at a dinner party
2. Taking log of pie sign gives summation sign
3. Simple/Compound Interest Comparison

March 31

Wikipedia:Reference_desk/Archives/Mathematics/2010 March 31

1. Variance