Mathematics
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Stefan
  • Member for 9 years, 10 months
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All Questions Answers
Score Newest
answer
31
Turning coins on a chessboard
Jul 9, 2017
answer
10
Prove that if $A$ is invertible matrix then $AA^T$ and $A^T A$ are also invertible.
Sep 20, 2012
answer
10
How does $3^n-1+2 \cdot 3^n$ evaluate to $3^{n+1}-1$?
Mar 20, 2013
answer
10
Prove that $H=0$ or $H=\mathbb{Q}$
Apr 23, 2013
answer
8
How does $2^{k+1} = 2 \times 2^k$?
Oct 30, 2012
question
7
Lie group structure of the tangent bundle
Mar 27, 2018
answer
7
How do I calculate $\lim_{x\rightarrow 0} x\ln x$
Feb 14, 2013
answer
7
Suppose that $f$ is a differentiable function such that $f(g(x)) = x$ and $f^\prime(x) = 1+ [f(x)]^2$. Show that $g^\prime(x) = \frac{1}{1+x^2}$.
Mar 17, 2015
answer
6
Derivative of $\arctan \sqrt x$
Mar 22, 2013
answer
5
Why does $\bigcup_{X \in \mathscr{P}(\mathbb{N})}X = \mathbb{N}$, instead of $\mathscr{P}(\mathbb{N})?$
Feb 24, 2013
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6
$X\perp Y \Leftrightarrow Y\perp r(X)$?
5
DotNet: Static variables in DLL
5
How powerful are second order interactions?

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