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  • Member for 9 years, 4 months
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22 votes

Proof (claimed) for Riemann hypothesis on ArXiv

17 votes
Accepted

Explain why catastrophic cancellation happens

12 votes

When is inverting a matrix numerically unstable?

10 votes
Accepted

Is $\det(I+AA^*) $ always be non-zero?

8 votes
Accepted

determinant diagonal zero symmetric matrix

8 votes

Are these two equalities equivalent: $ABA=0$ and $BA=0$?

6 votes
Accepted

Why $C[0,1]$ with $d_\infty$ is a complete space?

4 votes

Can someone please help me understand Implicit Differentiation?

4 votes
Accepted

Strange oscillations in Matlab

3 votes

Does the sequence $f_n(x_n)$ converge to $f(x)$?

3 votes

Computation of a limit involving a series (related to Poisson distribution)

3 votes

Probability of two people meeting in a given square grid.

3 votes
Accepted

If $(\lambda_n)_{n\in\mathbb N}$ is the eigenvalue sequence of a trace-class operator, can we show that $\sum_{n\in\mathbb N}\sqrt{\lambda_n}<\infty$?

3 votes

Examples of problems that are easier in the infinite case than in the finite case.

3 votes

Why in these matrices are $AB=BA$ not equal? What is the logic behind them?

3 votes
Accepted

How to solve the simple inverse Laplace transform of $\frac{-(s+5)}{5(s+1)}$.

3 votes
Accepted

Statistics- Set Notation

3 votes
Accepted

A question in Rudin's Real and Complex Analysis

3 votes

How would you explain why $e^{i\pi}+1=0$ to a middle school student?

3 votes

Show or prove that $\int_{-\infty}^{\infty}\frac{\sin(x)}{x} \mathrm{e}^{i \alpha x} \mathrm{d}x = \pi$

3 votes

Is it true that positive definite matrices generates all the symmetric matrices?

2 votes
Accepted

Let $W \subset V$ vector spaces, let $W'$ be the orthogonal complement of $W$. Show $\dim(W)+\dim(W')=\dim V$

2 votes
Accepted

What does straight line general equation coefficients a, b, c mean

2 votes

An inequality concerning restricted isometry property

2 votes
Accepted

Sequence $(a_n)$ s.t. $\sum a_n$ converges and $|\{k \in \{0,\dots, n\}: a_{k+1} > a_k\}|/n \to 1$?

2 votes
Accepted

Reference on Riesz representation theorem for $L^p(0,T,X)$ spaces.

2 votes
Accepted

Doubly infinite matrices $A=(a_{i,j})_{i,j=\infty}^{\infty}$

2 votes
Accepted

Proof that $ \sum_{i=1}^\infty a_n$ is converges almost surely.

2 votes
Accepted

Unsure of an inequality and a certain step in a proof that shows $\Vert f \ast K_\delta - f \Vert_p \to 0 \ \text{as} \ \delta \to 0$?

2 votes

Comparison principle for reaction-diffusion equation: See $0\leq u(x,t)\leq 1$ and $u\to 0$ faster than $s(t)$.