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JustANoob
  • Member for 4 years, 11 months
  • Last seen more than a week ago
  • Lund, Sweden
7 votes
2 answers
95 views

Prove that $\exists c > 0$ such that $||f||_2 \le c ||T(f)||_{\infty}$

5 votes
2 answers
4k views

Why do $A$ and $A^TA$ have the same row space?

4 votes
5 answers
237 views

Which points on the curve $5x^2+4xy+2y^2-6=0$ are closest to the origin.

4 votes
1 answer
105 views

Understanding weakly dense.

3 votes
1 answer
26 views

Redundancy in the definition of the resolvet set?

3 votes
1 answer
173 views

$\sigma(T)$ is finite $\iff \exists p\in P: p(T) = 0$

3 votes
0 answers
54 views

Show that $T$ is isometric and not surjective. Proof validation.

3 votes
1 answer
49 views

$T$ is continuous $\iff \forall (x_1, x_2,..), x_i \in X, x_i \to^w x \implies T(x_i) \to^w T(x)$

3 votes
2 answers
114 views

Spectrum of $Tf(x) := \frac{1}{x}\int_{0}^{x}f(t)dt $

3 votes
1 answer
114 views

Distribution of $Z_n=n \log\left(\frac{\max\left(X_{(n)},Y_{(n)}\right)}{\min\left(X_{(n)},Y_{(n)}\right)}\right)$

3 votes
1 answer
676 views

Prove strict convex norm equivalence

3 votes
1 answer
32 views

Exists an $h$ such that $\lVert u + hv \rVert_{\infty}= \max_{x \in U}|u(x)+hv(x)|$

3 votes
0 answers
80 views

Show that $Y_1$ and $Y_2$ are independent $N(0, 1)$-distributed random variables. [duplicate]

3 votes
2 answers
588 views

Distribution of $X\sqrt {2Y}$ where $X\sim N (0,1)$ and $Y\sim \operatorname{Exp} (1)$

2 votes
1 answer
66 views

Find the distribution of $Y$ given $p_{X}$ and $ p_{Y \mid X}$

2 votes
1 answer
446 views

Prove that the dimension of the eigenspace corresponding to the eigenvalue $\lambda=1$ of $H$ is at least the number of the clusters..

2 votes
1 answer
161 views

Calculate flux integral

2 votes
1 answer
531 views

Expected value of the total waiting time of all passengers catching a train.

2 votes
2 answers
110 views

Find different $f_1,f_2 \in F$ such that $\lVert f_1 \rVert = \lVert f_2 \rVert=1$ and $\lVert f_1 + f_2 \rVert =2$

2 votes
1 answer
96 views

Connected Dirichlet and Neumann conditions

2 votes
1 answer
58 views

Show that $\exists L \in (l^\infty)'$ such that $\forall f \in C([0,1]): \int\limits_{0}^{1}f(t)dt = L(T(f))$.

2 votes
0 answers
33 views

A matrix $A$ is $K$-irreducible if and only if no eigenvector lies on $\partial K$.

2 votes
1 answer
52 views

Dense and weakly dense, sequentially speaking.

2 votes
0 answers
26 views

Map bounded if composition is bounded. (Proof verification)

2 votes
2 answers
97 views

Probability of $x$ being rational

1 vote
1 answer
44 views

Equicontinuity, compactness and uniform convergence.

1 vote
0 answers
33 views

Show that $\dim(Z) < \infty$ if $Z \subset T(X)$ for compact $T$

1 vote
1 answer
61 views

Show that $T f(x) = \frac{1}{x^2}\int\limits_0^x t f(t) dt$ is not compact.

1 vote
1 answer
25 views

$\nexists y \in l^1$ such that $\forall x \in S: L(x) = \sum\limits_{n\ge 1}(x y)\lbrack n \rbrack$

1 vote
0 answers
25 views

References on nonnegative matrices