User pxc3110

7 votes

2 answers

6k views

How can you find all subgroups of a certain group?

asked Apr 7, 2014 at 8:46

5 votes

1 answer

2k views

General linear group and special linear group

asked Dec 17, 2014 at 20:01

4 votes

2 answers

216 views

Why $a^p\in N$ if $[a]^p=[e]$ holds in $G/N$

asked Apr 2, 2014 at 11:54

4 votes

2 answers

216 views

$G$ an abelian group, $n>1$ a fixed integer, and $\phi :G\to G$ defined by $\phi(a)=a^n$ for $a\in G$. Determine wheter $\phi$ is onto.

asked May 3, 2014 at 4:28

4 votes

3 answers

891 views

Show that the function $f:X\to \mathbb R$ defined by $f(x)=d(x,A)$ is continuous.

asked Jul 17, 2014 at 2:57

4 votes

1 answer

95 views

Then is $f_a$ continious?

asked Nov 21, 2014 at 2:42

4 votes

1 answer

165 views

Getting a wrong result when calculating $\int \frac{x^3}{\sqrt{1-x^8}}dx$

asked Dec 12, 2014 at 17:34

4 votes

0 answers

159 views

An example of regular singular points

asked Dec 17, 2014 at 16:18

3 votes

2 answers

2k views

derivative of a symmetric bilinear form (quadratic form version)

asked Dec 16, 2014 at 17:03

3 votes

2 answers

5k views

If every left coset of $H$ is a right coset the show that $H=aHa^{-1}$ for all a in G

asked Apr 24, 2014 at 12:08

3 votes

3 answers

4k views

If G is a finite abelian group and $a_1,...,a_n$ are all its elements, show that $x=a_1a_2a_3...a_n$must satisfy $x^2=e$.

asked Apr 25, 2014 at 2:49

3 votes

4 answers

4k views

Show that $G$ is a group if the cancellation law holds when identity element is not sure to be in $G$ [duplicate]

asked Apr 10, 2014 at 14:41

3 votes

3 answers

29k views

Show that if $f \circ g$ is surjective, then $f$ is surjective, and $g$, the function applied first, needs not to be.

asked Apr 12, 2014 at 9:31

3 votes

2 answers

903 views

Prove that the series still converges under a permutation

asked Feb 16, 2015 at 19:33

2 votes

1 answer

31 views

Suppose that $f$ is convergence preserving, then show that for some open neighbourhood of $0$, $f$ is antisymmetric w.r.t. the $y$ axis.

asked Feb 16, 2015 at 21:54

2 votes

3 answers

282 views

Prove: $\kappa^2v^4=|\alpha^{''}|^2-(\frac{dv}{dt})^2.$

asked Jan 2, 2015 at 1:16

2 votes

1 answer

730 views

Prove that the curvature of $\gamma$ is $\frac{\kappa_{\alpha}}{\sin^2\theta}$

asked Jan 2, 2015 at 4:20

2 votes

2 answers

151 views

Finding the interval of convergence of $\sum^{\infty}_{n=0}\frac{(2n)!}{(n!)^2}x^n$

asked Apr 13, 2015 at 17:03

2 votes

0 answers

465 views

Is the Hamiltonian conserved or not?

asked Nov 19, 2015 at 3:03

2 votes

3 answers

259 views

The meaning of $\bigcap_{x\in G} x^{-1}Hx$ and the proof for the fact that $N$ is a subgroup of $G$ such that $y^{-1}Ny=N$ for every $y\in G$

asked Apr 8, 2014 at 7:00

2 votes

0 answers

102 views

I study abstract algebra mainly because I'm planning to study relativity Please give me a guideline for learning this subject

asked Apr 7, 2014 at 12:49

2 votes

3 answers

1k views

Taylor Expansion for a Multivariable Function

asked Apr 13, 2014 at 5:57

2 votes

1 answer

212 views

Why ${(a^2)}^{\frac 12}=\sqrt {a^2}=|a| \neq a$?

asked Apr 21, 2014 at 9:15

2 votes

1 answer

82 views

Show that $f(x,y,z)=0$ if and only if $(\sqrt {x^2+y^2}-1)^2+z^2=r^2$.

asked Dec 16, 2014 at 21:00

2 votes

1 answer

212 views

Computing for $\theta$ component of the geodesic equation

asked Dec 5, 2014 at 10:48

2 votes

2 answers

1k views

Show that if $p$ is a prime of the form $p=4n+1$, then we can solve $x^2\equiv -1\mod p$(with $x$ an integer).

asked May 2, 2014 at 10:03

2 votes

0 answers

73 views

I was trying to compute the lie derivative and I didn't find my result in the options under the question

asked Nov 16, 2014 at 0:19

1 vote

2 answers

41 views

Then why $\lim_{x\to +\infty}f(x)=+\infty$?

asked Nov 13, 2014 at 22:16

1 vote

2 answers

183 views

Matrix representation of the derivative of a smooth function

asked Dec 17, 2014 at 16:46

1 vote

1 answer

71 views

Why then is $df(x)$ surjective if and only if $Ax\neq 0$?

asked Dec 16, 2014 at 18:46

Stack Exchange Network

98 Questions

How can you find all subgroups of a certain group?

General linear group and special linear group

Why $a^p\in N$ if $[a]^p=[e]$ holds in $G/N$

$G$ an abelian group, $n>1$ a fixed integer, and $\phi :G\to G$ defined by $\phi(a)=a^n$ for $a\in G$. Determine wheter $\phi$ is onto.

Show that the function $f:X\to \mathbb R$ defined by $f(x)=d(x,A)$ is continuous.

Then is $f_a$ continious?

Getting a wrong result when calculating $\int \frac{x^3}{\sqrt{1-x^8}}dx$

An example of regular singular points

derivative of a symmetric bilinear form (quadratic form version)

If every left coset of $H$ is a right coset the show that $H=aHa^{-1}$ for all a in G

If G is a finite abelian group and $a_1,...,a_n$ are all its elements, show that $x=a_1a_2a_3...a_n$must satisfy $x^2=e$.

Show that $G$ is a group if the cancellation law holds when identity element is not sure to be in $G$ [duplicate]

Show that if $f \circ g$ is surjective, then $f$ is surjective, and $g$, the function applied first, needs not to be.

Prove that the series still converges under a permutation

Suppose that $f$ is convergence preserving, then show that for some open neighbourhood of $0$, $f$ is antisymmetric w.r.t. the $y$ axis.

Prove: $\kappa^2v^4=|\alpha^{''}|^2-(\frac{dv}{dt})^2.$

Prove that the curvature of $\gamma$ is $\frac{\kappa_{\alpha}}{\sin^2\theta}$

Finding the interval of convergence of $\sum^{\infty}_{n=0}\frac{(2n)!}{(n!)^2}x^n$

Is the Hamiltonian conserved or not?

The meaning of $\bigcap_{x\in G} x^{-1}Hx$ and the proof for the fact that $N$ is a subgroup of $G$ such that $y^{-1}Ny=N$ for every $y\in G$

I study abstract algebra mainly because I'm planning to study relativity Please give me a guideline for learning this subject

Taylor Expansion for a Multivariable Function

Why ${(a^2)}^{\frac 12}=\sqrt {a^2}=|a| \neq a$?

Show that $f(x,y,z)=0$ if and only if $(\sqrt {x^2+y^2}-1)^2+z^2=r^2$.

Computing for $\theta$ component of the geodesic equation

Show that if $p$ is a prime of the form $p=4n+1$, then we can solve $x^2\equiv -1\mod p$(with $x$ an integer).

I was trying to compute the lie derivative and I didn't find my result in the options under the question

Then why $\lim_{x\to +\infty}f(x)=+\infty$?

Matrix representation of the derivative of a smooth function

Why then is $df(x)$ surjective if and only if $Ax\neq 0$?