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Methods for Finding Raw Moments of the Normal Distribution
I'm having some trouble with finding raw moments for the normal distribution. Right now I am trying to find the 4th raw moment on my own. So far, I k...
Apr 14, 2026
Archive: News
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Danskins' theorem
Suppose $\phi (x,z)$ is a continuous function of two arguments, $$\phi :{\mathbb {R} }^{n}\times Z\rightarrow {\mathbb {R} }$$ where $Z\subset {\mathbb {R...
Apr 14, 2026
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Decide whether DFA accepts all Strings
Wikipedia : Because DFAs can be reduced to a canonical form (minimal DFAs), there are also efficient algorithms to determine: whether a DFA accepts any st...
Apr 14, 2026
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Difference between Reflexive and Symmetric in Discrete Maths
Difference between Reflexive and Symmetric in Discrete Maths? This is what I understand: Reflexive -> <a,a=a>, <b,b=b> uses = to describe. Sym...
Apr 14, 2026
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Nice proofs of $\zeta(4) = \frac{\pi^4}{90}$?
I know some nice ways to prove that $\zeta(2) = \sum_{n=1}^{\infty} \frac{1}{n^2} = \pi^2/6$. For example, see Robin Chapman's list or the answers to...
Apr 14, 2026
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Choose $h$ and $k$ so that the system has no solution, one solution andinfinitely many
Choose $h$ and $k$ so that the system has no solution, one solution and infinitely many $x_1 + 3x_2 =2$ $3x_1 + hx_2 = k$ So I put it into a augmented mat...
Apr 14, 2026
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Can every even integer be expressed as the difference of two primes?
Can every even integer be expressed as the difference of two primes? If so, is there any elementary proof?
Apr 14, 2026
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On Riemann sums for negative exponents
Let $0 < a < b$. Use Riemann sums to compute $$ \int_{a}^{b}x^{-2}\ \mathrm{d}x\ . $$ So far, I have gotten to the step where \begin{align} \int_{a}...
Apr 14, 2026
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Fourier basis functions
What are Fourier basis functions? And how do I prove that Fourier basis functions are orthonormal?
Apr 14, 2026
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Vectors Definition
What is basically a vector ? I am not a starter in learning vectors , have used them in physics and mathematics and done with 1st year of my BS in physics...
Apr 14, 2026
