User MAS - Mathematics Stack Exchange

26 votes

3 answers

8k views

basic difference between canonical isomorphism and isomorphims

asked Apr 26, 2019 at 9:11

12 votes

1 answer

723 views

Finding polynomial without constant term that commutes with $f(x)=x^3+3x$

asked Dec 21, 2021 at 6:41

8 votes

2 answers

628 views

Show that $ \mathbb{Q}_3(i)$ is an unramified extension

asked Oct 9, 2018 at 11:50

7 votes

1 answer

388 views

What is the most common and appropriate definition of tensor? [closed]

asked Jul 24, 2019 at 8:17

7 votes

2 answers

1k views

Continued fraction of $\sqrt{67} - 4$

asked Apr 3, 2017 at 12:54

7 votes

1 answer

327 views

Which Hecke algebra is used in representation theory?

asked Jan 10, 2021 at 15:06

6 votes

2 answers

2k views

Why does the short exact sequence for projective module split?

asked Dec 25, 2020 at 17:59

6 votes

3 answers

1k views

Can we expand "induction principle" to a partial order $(X, \leq)$?

asked Mar 20, 2019 at 8:36

5 votes

1 answer

1k views

If A is a real non-singular square matrix, then there exists a real matrix $B$ such that $e^B$ $=$ $A^2$

asked Mar 12, 2019 at 17:57

5 votes

0 answers

199 views

Can someone explain why we take Second Countability and Hausdorffness conditions in Manifold definition? [duplicate]

asked May 6, 2019 at 7:38

5 votes

0 answers

102 views

Is the subspace $N=\{y\in l_\infty: y_k=x_k\ a.a.k,\ x\in M \}$ closed or not?

asked Jun 23, 2019 at 7:03

5 votes

1 answer

798 views

Is there concept of continuous curve and surfaces in p-adic field?

asked May 31, 2018 at 9:22

5 votes

3 answers

5k views

If J is a 101×101 matrix with all entries equal to 1 and let I denote the identity matrix of order 101. Then what is the determinant of J-I?

asked Dec 3, 2015 at 13:14

5 votes

3 answers

2k views

Show that $ h(x)=\max \{f(x,y) : y \in [0,1] \} $ is continuous

asked Oct 5, 2017 at 7:34

5 votes

1 answer

453 views

What is the $p$-adic valuation of $\zeta_p-1$?

asked Aug 13, 2020 at 19:18

5 votes

2 answers

441 views

Existence of a non-compact Riemannian manifold with infinite injective radius

asked Jan 3, 2020 at 12:54

5 votes

1 answer

533 views

How to introduce $p$-adic numbers to undergraduates?

asked Sep 24, 2022 at 13:40

4 votes

0 answers

1k views

What is the definition of $\text{weight or Hodge-Tate weight}$ in the p-adic Hodge theory?

asked Jan 4, 2020 at 16:27

4 votes

1 answer

196 views

how to calculate the norm of the above fields $K^{\times}$?

asked Dec 31, 2019 at 8:51

4 votes

1 answer

920 views

What is the Galois group of the polynomial $f(x)=x^3-3$ over $\mathbb{Q}$?

asked Aug 3, 2020 at 14:16

4 votes

1 answer

124 views

Why is $\text{Gal}(K/\mathbb{Q}) \cong G_{\mathbb{Q}}/{\{\sigma \in G_{\mathbb{Q}}: \ \sigma|_K=id_K \}}$?

asked Jul 16, 2020 at 17:40

4 votes

2 answers

68 views

Need help to check alternating series criterion

asked Dec 20, 2020 at 17:56

4 votes

0 answers

70 views

How to show that the full faithfulness of a functor preserved under an action of finite flat algebra?

asked Feb 1, 2021 at 12:49

4 votes

2 answers

230 views

Question from $p$-adic HodgeTheory, linear algebra data

asked Oct 27, 2020 at 10:19

4 votes

4 answers

181 views

$ 3^{2^n }- 1 $ is divisible by $ 2^{n+2} $

asked Sep 12, 2017 at 5:16

4 votes

4 answers

1k views

Extension of continuous map in topological space

asked Sep 12, 2017 at 12:29

4 votes

3 answers

289 views

Find the sum of the series $ \ \sum_{n=1}^{\infty} \frac{1}{n^2+l^2} \ $ [duplicate]

asked Nov 21, 2017 at 3:18

4 votes

1 answer

717 views

Is there any conclusion about a group, if the group has unique element of order $n>1$?

asked May 29, 2016 at 22:15

4 votes

3 answers

2k views

is there any convergent sub-sequence of a sequence of all rational numbers?

asked Jun 3, 2016 at 18:40

4 votes

3 answers

191 views

Evaluate the integral $\int_{0}^{\pi}\frac{\log(1+a\cos x)}{\cos x}\,dx$

asked Mar 18, 2017 at 16:59

Stack Exchange Network

877 Questions

basic difference between canonical isomorphism and isomorphims

Finding polynomial without constant term that commutes with $f(x)=x^3+3x$

Show that $ \mathbb{Q}_3(i)$ is an unramified extension

What is the most common and appropriate definition of tensor? [closed]

Continued fraction of $\sqrt{67} - 4$

Which Hecke algebra is used in representation theory?

Why does the short exact sequence for projective module split?

Can we expand "induction principle" to a partial order $(X, \leq)$?

If A is a real non-singular square matrix, then there exists a real matrix $B$ such that $e^B$ $=$ $A^2$

Can someone explain why we take Second Countability and Hausdorffness conditions in Manifold definition? [duplicate]

Is the subspace $N=\{y\in l_\infty: y_k=x_k\ a.a.k,\ x\in M \}$ closed or not?

Is there concept of continuous curve and surfaces in p-adic field?

If J is a 101×101 matrix with all entries equal to 1 and let I denote the identity matrix of order 101. Then what is the determinant of J-I?

Show that $ h(x)=\max \{f(x,y) : y \in [0,1] \} $ is continuous

What is the $p$-adic valuation of $\zeta_p-1$?

Existence of a non-compact Riemannian manifold with infinite injective radius

How to introduce $p$-adic numbers to undergraduates?

What is the definition of $\text{weight or Hodge-Tate weight}$ in the p-adic Hodge theory?

how to calculate the norm of the above fields $K^{\times}$?

What is the Galois group of the polynomial $f(x)=x^3-3$ over $\mathbb{Q}$?

Why is $\text{Gal}(K/\mathbb{Q}) \cong G_{\mathbb{Q}}/{\{\sigma \in G_{\mathbb{Q}}: \ \sigma|_K=id_K \}}$?

Need help to check alternating series criterion

How to show that the full faithfulness of a functor preserved under an action of finite flat algebra?

Question from $p$-adic HodgeTheory, linear algebra data

$ 3^{2^n }- 1 $ is divisible by $ 2^{n+2} $

Extension of continuous map in topological space

Find the sum of the series $ \ \sum_{n=1}^{\infty} \frac{1}{n^2+l^2} \ $ [duplicate]

Is there any conclusion about a group, if the group has unique element of order $n>1$?

is there any convergent sub-sequence of a sequence of all rational numbers?

Evaluate the integral $\int_{0}^{\pi}\frac{\log(1+a\cos x)}{\cos x}\,dx$