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Mar
19
awarded  Sportsmanship
Mar
18
revised Solving an equation $\pmod {13}$
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Mar
18
answered Solving an equation $\pmod {13}$
Mar
18
reviewed Leave Open The n-envelope problem
Mar
18
reviewed Close How to integrate this expression?
Mar
18
reviewed Close Most efficient way to learn mathematics
Mar
18
reviewed Close What does it take to get a job at a top 50 math program in the U.S.?
Mar
18
reviewed Leave Open General question about mathematical thinking
Mar
18
reviewed Close How to do well in higher level math classes
Mar
18
reviewed Leave Open Norm of some element in cyclotomic field
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18
reviewed Leave Open Is Topology an important class to take before Functional Analysis?
Mar
18
reviewed Leave Open When writing a mathematical model for non-mathematical audiences, how do you begin a sentence defining a variables and parameters?
Mar
18
reviewed Leave Open Why is this true ? $(1-s)\zeta(s) = \sum_{k=0}^\infty \frac{\Gamma(k+1-s/2) A_k}{\Gamma(1-s/2) k!}$
Mar
18
reviewed Leave Open Affine hull example
Mar
18
comment How to change the bounds of this iterated integral?
Do a few example and you'll quickly get the hang of it.
Mar
18
comment How to change the bounds of this iterated integral?
You first want to write down the inequalities which the old bounds imply for $x$ and $y$. You notice that the inequality for $x$ depends on $y$. Now you want to transform them into an equivalent pair of inequalities where the inequality for $x$ doesn't depend on $y$ anymore, but instead the one for $y$ depends on $x$. So you go $0\le x\le \sqrt{y}\le \sqrt{9}=3$ and you have the one for $x$. Now the one for $y$ follows b/c $0\le x\le \sqrt{y}$ is equivalent to $0\le x^2\le y$, and we also know $y\le 9$, so the inequality for $y$ is $x^2\le y\le 9$.
Mar
18
answered How to change the bounds of this iterated integral?
Mar
17
revised How would you prove that $2^{n-1} > n!$?
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Mar
17
answered How would you prove that $2^{n-1} > n!$?
Mar
17
comment Schwarz 's lemma and sharp upper bound
Yes, the function should be a Möbius transform. Try the one I gave you with suitable $z_0$....