User Cornman

7 votes

3 answers

2k views

$X^4-4X^2-1$ irreducible over $\mathbb{Q}[X]$

asked Sep 26, 2017 at 22:51

7 votes

2 answers

2k views

Continuous bijection which is not a homeomorphism.

asked Sep 1, 2018 at 17:19

7 votes

4 answers

9k views

Compact metric space and convergent subsequence

asked Aug 24, 2019 at 1:19

5 votes

2 answers

621 views

Why constant symbols in a language?

asked Apr 15, 2019 at 23:16

5 votes

1 answer

515 views

$\alpha\in\mathbb{C}$ algebraic over $\mathbb{Q}$ iff $\alpha^n$ algebraic over $\mathbb{Q}$

asked Sep 24, 2017 at 17:46

5 votes

2 answers

265 views

$f$ is continuous, if $f_n$ continuous and $f_n\to f$ uniformly

asked Jul 17, 2018 at 18:38

5 votes

1 answer

2k views

Linear function, that is not continuous?

asked Jul 18, 2018 at 18:11

5 votes

1 answer

260 views

Playing with the Möbius strip... mathematically

asked Jun 12, 2020 at 21:49

5 votes

1 answer

882 views

Guide to Modular Forms

asked May 21, 2021 at 15:32

4 votes

0 answers

187 views

Problem set to accompany "A Course in Arithmetic"

asked Oct 22, 2021 at 1:58

4 votes

2 answers

175 views

Integral inequality, proof verification

asked Dec 30, 2021 at 21:14

4 votes

0 answers

235 views

Current State of Knowledge: Riemann Hypothesis

asked Jul 22, 2022 at 0:48

4 votes

3 answers

1k views

Taylor series of $\sqrt{1+x}$ [duplicate]

asked May 27, 2018 at 13:09

4 votes

1 answer

1k views

$(c_0, \|\cdot \|_\infty)$ is a banach-space [duplicate]

asked Oct 26, 2017 at 3:31

4 votes

0 answers

259 views

Surface of the cube, differentiable manifold

asked Apr 23, 2017 at 14:50

4 votes

2 answers

771 views

multidimensional chain rule, example

asked Aug 20, 2018 at 1:33

4 votes

0 answers

4k views

Continuous bijection is homeomorphism

asked Aug 12, 2018 at 8:18

4 votes

1 answer

1k views

weights of Gaussian quadrature rule, numerical integration, reference request

asked May 5, 2019 at 23:53

3 votes

2 answers

145 views

$\|A\|_\infty = \sup_{x\neq 0} \frac{\|Ax\|_\infty}{\|x\|_\infty}=\|A\operatorname{1}\|_\infty$

asked Jun 23, 2019 at 19:13

3 votes

2 answers

97 views

universal property of product metric, proof explanation

asked Jul 13, 2019 at 1:34

3 votes

1 answer

223 views

Midpoint rule, error estimation for $f\in C^2$

asked May 5, 2019 at 22:52

3 votes

1 answer

129 views

Induction for L-terms equal to 'general' induction?

asked Sep 9, 2019 at 23:08

3 votes

1 answer

2k views

Compact subset in a Hausdorff space, is closed.

asked Jul 21, 2018 at 15:48

3 votes

1 answer

451 views

Neighbourhood, French railroad metric

asked Jan 31, 2019 at 3:35

3 votes

3 answers

2k views

Quotient topology, finest topology

asked Apr 24, 2017 at 19:33

3 votes

1 answer

96 views

Functional analysis,$\ell^p$, continuous and uncontinuous operator

asked Nov 2, 2017 at 15:10

3 votes

0 answers

152 views

Schwartz space, functional analysis

asked Nov 16, 2017 at 17:59

3 votes

1 answer

473 views

Hahn-Banach, functional analysis, linear subspace, restricted norm

asked Nov 22, 2017 at 3:17

3 votes

2 answers

703 views

$\ell^\infty(\mathbb{N})$ is not separable [duplicate]

asked Nov 26, 2017 at 10:55

3 votes

2 answers

2k views

Equivalent metrics generate the same topology

asked Jul 15, 2018 at 1:38

Stack Exchange Network

197 Questions

$X^4-4X^2-1$ irreducible over $\mathbb{Q}[X]$

Continuous bijection which is not a homeomorphism.

Compact metric space and convergent subsequence

Why constant symbols in a language?

$\alpha\in\mathbb{C}$ algebraic over $\mathbb{Q}$ iff $\alpha^n$ algebraic over $\mathbb{Q}$

$f$ is continuous, if $f_n$ continuous and $f_n\to f$ uniformly

Linear function, that is not continuous?

Playing with the Möbius strip... mathematically

Guide to Modular Forms

Problem set to accompany "A Course in Arithmetic"

Integral inequality, proof verification

Current State of Knowledge: Riemann Hypothesis

Taylor series of $\sqrt{1+x}$ [duplicate]

$(c_0, \|\cdot \|_\infty)$ is a banach-space [duplicate]

Surface of the cube, differentiable manifold

multidimensional chain rule, example

Continuous bijection is homeomorphism

weights of Gaussian quadrature rule, numerical integration, reference request

$\|A\|_\infty = \sup_{x\neq 0} \frac{\|Ax\|_\infty}{\|x\|_\infty}=\|A\operatorname{1}\|_\infty$

universal property of product metric, proof explanation

Midpoint rule, error estimation for $f\in C^2$

Induction for L-terms equal to 'general' induction?

Compact subset in a Hausdorff space, is closed.

Neighbourhood, French railroad metric

Quotient topology, finest topology

Functional analysis,$\ell^p$, continuous and uncontinuous operator

Schwartz space, functional analysis

Hahn-Banach, functional analysis, linear subspace, restricted norm

$\ell^\infty(\mathbb{N})$ is not separable [duplicate]

Equivalent metrics generate the same topology