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21
Calculating $\lim_{n\to\infty}\sqrt{n}\sin(\sin...(\sin(x)..)$
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17
How to prove that the rank of a matrix is a lower semi-continuous function?
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14
Can a symmetric matrix always be represented as the sum of a positive-definite and negative-definite matrix?
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11
Measurable function remaining constant
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9
Summation of $\sum\limits_{n=1}^{\infty} \frac{x(x+1) \cdots (x+n-1)}{y(y+1) \cdots (y+n-1)}$
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9
limit of the sum $\frac{1}{n+1}+\frac{1}{n+2}+\cdots+\frac{1}{2n} $
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9
The meaning behind $(X^TX)^{-1}$
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6
Consider the following sequence defined as follows:
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6
Does $\sum_k \frac{a_k-a_{k-1}}{a_k^2}$ converge if $a_k \uparrow \infty$?
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6
How to study $\sum_{n=2}^\infty \ln(1 + 3/n + 3/n^2 + 1/n^3)$
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5
How to prove this binomial identity $\sum_{r=0}^n {r {n \choose r}} = n2^{n-1}$?
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5
Understanding dominating functions
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5
is $f$ surjective from $\mathbb{R}\rightarrow\mathbb{R}$
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5
Does this $3\times 3$ matrix exist?
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5
If $\operatorname{rk}(A) = 1$, when $B + A$ is invertible?
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5
How to write $ uv^{\top} + vu^{\top} $ as $ xx^{\top} + yy^{\top} $?
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5
Printing beamer slides?
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5
$\lambda^2$ is an eigenvalue of $A^2$. Prove that $\lambda$ or $-\lambda$ is an eigenvalue of the matrix $A$
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