Recent content by ialbrekht

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    How do I determine the volume of a revolved area using integrals?

    To find area between two functions you have to find integral of module of differences of them. But in current situation it's a bit easier: sin(x) > -sin(x) on [0, \pi] v = \int_o^\pi sin(x)-(-sin(x)) dx = 2 \int_0^\pi sin(x) dx My English is also not really good :wink:
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    MATLAB Computing the area under a curve with Matlab

    Hi Faiza, If you have only few point of your curve, than you may use two ways: 1. Find approximation polynomial and than evaluate integral; 2. Just use following formula (by integral definition): \sum_{i=1}^{n-1} f_i(x_{i+1}-x_i) , where f_i=f(x_i) There are some other methods you may...
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    Is there a simple way to determine if an element is a primitive root modulo n?

    robert Ihnot: Thanks for correcting me. It's the first method I've remembered. The hardest thing is to factorize P-1, and It's not a problem for a not large P and if you know factorization of P-1 you may check g to be primitive root for polynomial time. And I did not say that it's EASY...
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    Is 0.9999... Equal to 1? Debunking the Myth and Understanding the Concept

    0.99999(9) is 1 It's right and logical. Unfortunately, I don't remember the prove now, it was on the first grade in University.
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    Which books are recommended for learning about RSA public-key cryptography?

    http://www.schneier.com/book-applied.html and http://www.cacr.math.uwaterloo.ca/hac/ You may download second book online from the like below.
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    Divisor Function t(n): Proving $2n*(n)^{1/2}$

    Dodo: You started in interesting direction, but f(n) = k! where k=\sum(k_i) Let's start iterative theorem prove: k=1 then t(n)=1 and 1<2\sqrt{n} for any n>1. Prove for k+1 t(n)=(k+1)!=k!(k+1) Now we have to prove that k!(k+1) < 2\sqrt{n} Let's suppose that it's not true. Divide both...
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    Is there a simple way to determine if an element is a primitive root modulo n?

    Hi, there is one method but it required knowing expansion of the number P-1 on the simple factors. So, if P-1 = p_{1}^{a_1} \times \cdots \times p_{n}^{a_n} where each p_i is prime and for each i=1...n : \frac{g^{P-1}}{p_i} \equiv 1 (mod P), than g - is primitive root (generator) by modulo...
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