User Myshkin

4 votes

2 answers

2k views

sum of two connected subset of $\mathbb{R}$

asked Dec 14, 2012 at 7:28

4 votes

2 answers

932 views

fixed point of homeomorphism and compactness of a complete metric space.

asked Dec 12, 2012 at 18:08

4 votes

1 answer

2k views

Invariant subspaces of specific dimension

asked Nov 21, 2012 at 9:20

4 votes

1 answer

97 views

$\dim$ $C(X,\mathbb{R})<\infty$ we need to show $|X|<\infty$,

asked Feb 7, 2013 at 11:24

4 votes

4 answers

1k views

find a $n\times n$ real matrix whose minimal polynomial is $x^{n-1}$

asked Jan 29, 2013 at 11:56

4 votes

1 answer

281 views

a question on transcendental entire function

asked Mar 7, 2013 at 3:59

4 votes

2 answers

162 views

To show $\lim_{x \to \infty} \int_{x}^{x+1}f(t)dt=0$ if $\lim_{x\to\infty} f(x)=0$

asked Jan 13, 2013 at 9:53

4 votes

0 answers

132 views

an application of implicit function theorem?

asked Jan 23, 2013 at 1:53

4 votes

1 answer

541 views

a doubt on manifold with boundary, critical point, space of jets etc

asked Jan 24, 2013 at 5:19

4 votes

1 answer

319 views

$|f(z)|\le 1-|z|\forall z\in D$, we need to show $f\equiv 0$

asked Jan 27, 2013 at 6:33

4 votes

1 answer

269 views

For $f$ an analytic function, what is

asked Jun 14, 2013 at 16:48

4 votes

1 answer

99 views

$f : \mathbb{R} \to \mathbb{R}$ be injective then $f^{ −1} (\mathbb{Q} \cap [0, 1])$ is

asked Jun 7, 2013 at 16:57

4 votes

1 answer

691 views

A linear transformation which maps the unit sphere to itself.

asked Jun 22, 2013 at 10:55

4 votes

2 answers

615 views

Sequence $f_n$ of continuous functions on $[0,1]$, such that $0 \le f_n \le 1$ and $\lim\limits_{n\to\infty}\int_{0}^{1} f_n(x)\,\mathrm dx=0$

asked Jun 21, 2013 at 17:23

4 votes

3 answers

556 views

$A$ be a $2\times 2$ real matrix with trace $2$ and determinant $-3$

asked May 25, 2013 at 3:01

4 votes

1 answer

190 views

vector space generated by $\{I,A,A^2,\dots,A^{2n}\}$

asked May 25, 2013 at 6:40

4 votes

1 answer

163 views

Given $x,y\in\mathbb{C}^n$ s.t. $f(x,y)=\sup_{\theta,\phi}\{\|e^{i\theta}x-e^{i\phi}y\|^2,\theta,\phi\in\mathbb{R}\}$ [duplicate]

asked May 27, 2013 at 4:25

4 votes

2 answers

406 views

$f:\mathbb{R}\to\mathbb{R}$ is continuous and $\int_{0}^{\infty} f(x)dx$ exists [duplicate]

asked May 30, 2013 at 16:35

4 votes

3 answers

5k views

$f(x)=|\cos x|+|\sin(2-x)|$ at which of the following point $f$ is not differentiable?

asked May 22, 2013 at 11:09

4 votes

2 answers

193 views

$f$ be a continous function on $\mathbb{R}$ with period $1$

asked Apr 25, 2013 at 10:31

4 votes

2 answers

233 views

$A^3+A=0$ We need to show $\mathrm{rank}(A)=2$

asked May 13, 2013 at 3:34

4 votes

3 answers

3k views

$\mathbb{Q}/\mathbb{Z}$ has cyclic subgroup of every positive integer $n$? [duplicate]

asked May 14, 2013 at 12:21

4 votes

3 answers

16k views

Length of curve in 3D spherical coordinate

asked Mar 12, 2013 at 7:10

4 votes

4 answers

182 views

to show $X$ is disconnected

asked Mar 19, 2013 at 10:45

4 votes

3 answers

627 views

$|f(x)-f(y)|\le g(x-y)$, is $f$ continous when $g$ is

asked Apr 7, 2017 at 14:15

4 votes

1 answer

148 views

how to find such matrices to compute $\sin A$

asked Apr 28, 2018 at 8:09

4 votes

1 answer

182 views

can a subspace of $\mathbb{R}^n$ lies only on the positive orthant?

asked Jun 24, 2018 at 10:34

4 votes

1 answer

110 views

Quartic function in four variables

asked Mar 28, 2020 at 11:15

4 votes

1 answer

370 views

conditions for which matrix has all eigenvalues inside unit circle or on the unit circle

asked Feb 12, 2021 at 21:54

4 votes

3 answers

3k views

$a,b,c,p$ are rational number and $p$ is not a perfect cube

asked Apr 22, 2015 at 3:32

Stack Exchange Network

1,119 Questions

sum of two connected subset of $\mathbb{R}$

fixed point of homeomorphism and compactness of a complete metric space.

Invariant subspaces of specific dimension

$\dim$ $C(X,\mathbb{R})<\infty$ we need to show $|X|<\infty$,

find a $n\times n$ real matrix whose minimal polynomial is $x^{n-1}$

a question on transcendental entire function

To show $\lim_{x \to \infty} \int_{x}^{x+1}f(t)dt=0$ if $\lim_{x\to\infty} f(x)=0$

an application of implicit function theorem?

a doubt on manifold with boundary, critical point, space of jets etc

$|f(z)|\le 1-|z|\forall z\in D$, we need to show $f\equiv 0$

For $f$ an analytic function, what is

$f : \mathbb{R} \to \mathbb{R}$ be injective then $f^{ −1} (\mathbb{Q} \cap [0, 1])$ is

A linear transformation which maps the unit sphere to itself.

Sequence $f_n$ of continuous functions on $[0,1]$, such that $0 \le f_n \le 1$ and $\lim\limits_{n\to\infty}\int_{0}^{1} f_n(x)\,\mathrm dx=0$

$A$ be a $2\times 2$ real matrix with trace $2$ and determinant $-3$

vector space generated by $\{I,A,A^2,\dots,A^{2n}\}$

Given $x,y\in\mathbb{C}^n$ s.t. $f(x,y)=\sup_{\theta,\phi}\{\|e^{i\theta}x-e^{i\phi}y\|^2,\theta,\phi\in\mathbb{R}\}$ [duplicate]

$f:\mathbb{R}\to\mathbb{R}$ is continuous and $\int_{0}^{\infty} f(x)dx$ exists [duplicate]

$f(x)=|\cos x|+|\sin(2-x)|$ at which of the following point $f$ is not differentiable?

$f$ be a continous function on $\mathbb{R}$ with period $1$

$A^3+A=0$ We need to show $\mathrm{rank}(A)=2$

$\mathbb{Q}/\mathbb{Z}$ has cyclic subgroup of every positive integer $n$? [duplicate]

Length of curve in 3D spherical coordinate

to show $X$ is disconnected

$|f(x)-f(y)|\le g(x-y)$, is $f$ continous when $g$ is

how to find such matrices to compute $\sin A$

can a subspace of $\mathbb{R}^n$ lies only on the positive orthant?

Quartic function in four variables

conditions for which matrix has all eigenvalues inside unit circle or on the unit circle

$a,b,c,p$ are rational number and $p$ is not a perfect cube