User Annalisa

6 votes

5 answers

391 views

What are significant differences between polynomial rings and the ring of formal power series?

asked Jun 24, 2021 at 15:18

3 votes

0 answers

43 views

Question about homomorphism of algebras

abstract-algebra polynomials algebras

asked Jun 8, 2021 at 21:41

3 votes

2 answers

65 views

Find a $T_pM$ and $N_pM$

smooth-manifolds vector-bundles submanifold tangent-spaces

asked Nov 22, 2020 at 21:25

3 votes

3 answers

219 views

Same minimal polynomial gives isomorphism

abstract-algebra solution-verification

asked Nov 23, 2021 at 21:22

2 votes

2 answers

36 views

Solve the Integral in the following set

integration multiple-integral

asked Feb 7, 2021 at 10:11

2 votes

2 answers

40 views

Would the following sum give me the following numbers?

summation

asked Apr 23, 2021 at 19:09

2 votes

2 answers

92 views

Prove that a function $u: u= \ln\|x\|{_{2}}$ has $\Delta u = 0$.

real-analysis ordinary-differential-equations analysis functions

asked Jun 9, 2020 at 21:50

2 votes

0 answers

48 views

Let A be $A=${$xy:x \in (0; 1/2),y \in \mathbb{Z}, |y|<3$}. Which is the value of $\inf A+\sup A$?

real-analysis elementary-set-theory supremum-and-infimum

asked Sep 22, 2020 at 12:05

2 votes

1 answer

59 views

Calculate the following Integral $\int_{0}^{\infty} \frac{|\sin(\pi*x)|}{\lfloor x \rfloor} dx$

real-analysis integration

asked Oct 4, 2020 at 9:51

2 votes

2 answers

59 views

Questions about following proof regarding why $\mathbb{Z}[x]$ is not a principal ideal domain

abstract-algebra proof-explanation principal-ideal-domains

asked Jun 8, 2021 at 19:08

2 votes

0 answers

58 views

Are the following embeddings of the graph $K_{5}$ in the Möbius strip correct?

graph-theory mobius-band

asked Oct 24, 2021 at 19:11

2 votes

2 answers

145 views

Tables of $\mathbb{Z}/6\mathbb{Z}$ and $\mathbb{Z}/2\mathbb{Z} \times \mathbb{Z}/3\mathbb{Z}$?

abstract-algebra group-theory

asked Nov 8, 2021 at 21:09

1 vote

1 answer

61 views

What does this step in the following matrix algorithm mean?

matrices algorithms smith-normal-form

asked Nov 9, 2021 at 20:14

1 vote

0 answers

80 views

Find irreducible polynomials of degree 3 and 4 in $\mathbb{F}_{11}[x]$

abstract-algebra polynomials finite-fields irreducible-polynomials

asked Feb 9 at 16:37

1 vote

2 answers

59 views

Solve following ODE $(1-x^2)y''-xy'-2=0$

ordinary-differential-equations power-series

asked Mar 7 at 19:14

1 vote

1 answer

62 views

Is $\mathbb{C}[x,y]/(x^2+y)$ a UFD?

abstract-algebra unique-factorization-domains

asked Oct 26, 2021 at 18:26

1 vote

1 answer

38 views

Find all linear integer relations of following vectors

abstract-algebra modules

asked Jun 27, 2021 at 17:33

1 vote

1 answer

200 views

The identity map in two metric spaces is a homeomorphism

metric-spaces

asked Nov 17, 2020 at 11:32

1 vote

2 answers

98 views

Find all the solutions of the equation $x^3=2$ in the field $\mathbb F_{25}$

abstract-algebra field-theory finite-fields

asked Apr 7, 2021 at 19:08

1 vote

4 answers

94 views

Show that following modules are isomorphic

abstract-algebra modules module-isomorphism

asked Jun 1, 2021 at 17:19

1 vote

1 answer

57 views

Lattice in $\mathbb{R}^3$

abstract-algebra modules integer-lattices

asked May 8, 2021 at 12:20

1 vote

1 answer

119 views

When does lattice equal the whole $\mathbb{Z}^n$

abstract-algebra ring-theory integer-lattices

asked May 13, 2021 at 18:22

1 vote

0 answers

79 views

Prove the following identity (Fibonacci) using induction [duplicate]

summation solution-verification induction fibonacci-numbers

asked May 14, 2021 at 17:43

1 vote

1 answer

46 views

Are the following modules free and/or isomorphic?

abstract-algebra modules free-modules

asked May 15, 2021 at 9:14

1 vote

1 answer

57 views

Show that the following set defines a Topology in X

general-topology

asked Oct 20, 2020 at 17:49

1 vote

3 answers

166 views

Calculate the value of the following limit

real-analysis limits

asked Sep 24, 2020 at 9:16

1 vote

1 answer

47 views

Find the critical points of the function $f(x,y)=(y-x^2)(y-2x^2)$ and examine if they are local extremums.

real-analysis multivariable-calculus extreme-value-theorem

asked Jun 14, 2020 at 17:53

1 vote

2 answers

57 views

Checking the convergence of the improper integral

real-analysis convergence-divergence improper-integrals solution-verification

asked Jun 21, 2020 at 16:45

1 vote

0 answers

38 views

Prove that the function $u= \|x\|{_{2}^{2-n}} $ has $\Delta u = 0 $?

calculus analysis partial-differential-equations partial-derivative

asked Jun 1, 2020 at 10:42

1 vote

2 answers

43 views

Let $a_{n} \in \mathbb N $ be a sequence and $a_{n}\rightarrow +\infty$. Which of the following sentences is correct.

real-analysis sequences-and-series

asked Sep 18, 2020 at 8:46

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82 Questions

What are significant differences between polynomial rings and the ring of formal power series?

Question about homomorphism of algebras

Find a $T_pM$ and $N_pM$

Same minimal polynomial gives isomorphism

Solve the Integral in the following set

Would the following sum give me the following numbers?

Prove that a function $u: u= \ln\|x\|{_{2}}$ has $\Delta u = 0$.

Let A be $A=${$xy:x \in (0; 1/2),y \in \mathbb{Z}, |y|<3$}. Which is the value of $\inf A+\sup A$?

Calculate the following Integral $\int_{0}^{\infty} \frac{|\sin(\pi*x)|}{\lfloor x \rfloor} dx$

Questions about following proof regarding why $\mathbb{Z}[x]$ is not a principal ideal domain

Are the following embeddings of the graph $K_{5}$ in the Möbius strip correct?

Tables of $\mathbb{Z}/6\mathbb{Z}$ and $\mathbb{Z}/2\mathbb{Z} \times \mathbb{Z}/3\mathbb{Z}$?

What does this step in the following matrix algorithm mean?

Find irreducible polynomials of degree 3 and 4 in $\mathbb{F}_{11}[x]$

Solve following ODE $(1-x^2)y''-xy'-2=0$

Is $\mathbb{C}[x,y]/(x^2+y)$ a UFD?

Find all linear integer relations of following vectors

The identity map in two metric spaces is a homeomorphism

Find all the solutions of the equation $x^3=2$ in the field $\mathbb F_{25}$

Show that following modules are isomorphic

Lattice in $\mathbb{R}^3$

When does lattice equal the whole $\mathbb{Z}^n$

Prove the following identity (Fibonacci) using induction [duplicate]

Are the following modules free and/or isomorphic?

Show that the following set defines a Topology in X

Calculate the value of the following limit

Find the critical points of the function $f(x,y)=(y-x^2)(y-2x^2)$ and examine if they are local extremums.

Checking the convergence of the improper integral

Prove that the function $u= \|x\|{_{2}^{2-n}} $ has $\Delta u = 0 $?

Let $a_{n} \in \mathbb N $ be a sequence and $a_{n}\rightarrow +\infty$. Which of the following sentences is correct.