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Daniel Li
  • Member for 6 years, 8 months
  • Last seen more than 1 year ago
  • Cambridge, MA, USA
2 votes

The alternating group is a normal subgroup of the symmetric group

2 votes

Absolute value in integrating factor of First-Order Linear Differential Equation

2 votes

Prerequisites to reading *Convergence of Probability Measures* by Patrick Billingsley.

2 votes

Eigenvectors of real symmetric matrices are orthogonal

2 votes

Prove that $\operatorname{trace}(A^TA) = 0\ \iff\ A = 0$.

2 votes

Expected maximum of sub-Gaussian

2 votes
Accepted

Prove inequality $\|Z\|_2\le \|Z\|_1^{1/4} \|Z\|_3^{3/4}$

2 votes

Show that $\|uv^T-wz^T\|_F^2\le \|u-w\|_2^2+\|v-z\|_2^2$

2 votes

Gaussian width vs. Gaussian complexity

2 votes

Matrices commute if and only if they share a common basis of eigenvectors?

2 votes

Banach fixed point theorem with lip constant possibly attaining $1$

2 votes

Show that $\max$ function on $\mathbb R^n$ is convex

1 vote

Gaussian width of sparse balls

1 vote

Tricky convex hull problem

1 vote

Show that $\left. \frac{d}{dp}\right|_{p=1} \left[ \int f^p \, d\mu \right]^{1/p} =\int f \log(f) \, d\mu$

1 vote

Prove $n\Bbb Z/m\Bbb Z \cong\Bbb Z/(m/n)\Bbb Z$, where $n\mid m$

1 vote

Why does the identity $\mathbb{E}(X) = \mathbb{E}\left(\int \mathbb{1}_{u \leq X}du\right)$ hold?

1 vote

Factor functions into multiplicative factors

1 vote

Proof of inequality in Weierstrass approximation theorem proof through probability

1 vote

Dudley's integral inequality: tail bound

1 vote

Taking Seats on a Plane

1 vote

"Surface Area" of $k$ simplex in $\mathbb{R}^{k}$?

1 vote

Any Nilpotent Matrix is not Diagonalizable

1 vote

Cardinality of real bijective functions/injective functions from $\mathbb{R}$ to $\mathbb{R}$

1 vote

if $p\mid a$ and $p\mid b$ then $p\mid \gcd(a,b)$

1 vote

Slutsky's theorem for random matrices

1 vote

A short but tricky question on Sylow theorem and semidirect product

0 votes
Accepted

Prove following summation equality (convolution power)

0 votes

MISSISSIPPI combinations with the S's separated

0 votes

Existence of nontrivial normal subgroups in solvable finite groups