Mihail's user avatar
Mihail's user avatar
Mihail's user avatar
Mihail
  • Member for 9 years, 2 months
  • Last seen this week
5 votes
Accepted

Mean value inequality geometrical interpretaion

4 votes
Accepted

A sequence in a Hausdorff space and in a space that is not Hausdorff.

4 votes

Homology Whitehead theorem for non simply connected spaces

4 votes
Accepted

On the natural homomorphism $\nu:R\longrightarrow S^{-1}R$

4 votes

Local homeo is not a closed map

3 votes
Accepted

If the fiber and the base are parallelizable then so is the total space?

3 votes

Must a surjective continuous map on a compact space into itself be injective?

3 votes

Flipping the torus coordinates

3 votes

Possible groups for fundamental group of $\mathbb{R}$

3 votes
Accepted

Identify and sketch the locus ${\mathop{\rm Re}\nolimits} \bigl( {{{z + i} \over {z - i}}} \bigr) = 1$.

2 votes
Accepted

Show that $H$ is normal subgroup of $G$.

2 votes

How can a matrix relation be both antisymmetric and symmetric? Explain this image to me.

2 votes

Prove that $\lim_{x \to \frac{2}{\pi}}\lfloor \sin \frac{1}{x} \rfloor=0$ in the $\epsilon$-$\delta$ way

2 votes
Accepted

Induction: $\sum_{k=1}^{2n} (-1)^k k = n$

2 votes

Show that for any $a,b\in\mathbb{Z}$, $p$ prime: $(a^p+b^p)^{p^2}\equiv a+b \pmod p$

2 votes

What is the derivative of $\ln|x|$?

2 votes
Accepted

how to find this function $f(x)$ satisfying these conditions?

2 votes
Accepted

When an odd polynomial is a one-one map on $\mathbb{R}$

2 votes
Accepted

Example of a non-orientable 3-manifold

2 votes
Accepted

Calculation of the first Chern class of the canonical line bundle over $\mathbb{CP}^n$

2 votes

Are those statements Tautology?

2 votes

What is $\tan(\alpha+2\beta)\tan(2\alpha+\beta)$, if $\sin(\alpha+\beta) = 1$ and $\sin(\alpha-\beta) = \frac 12$

2 votes

The fundamental group(s) of $\Bbb Q$ and of $\Bbb R$.

2 votes

Is $A\times B\times C$ equal to $(A\times B)\times C$?

2 votes

Surjectivity of $H_1(X) \to H_1(X,A)$ for pathwise connected $A$

1 vote
Accepted

How taking plus or minus square root works, specifically for inequality?

1 vote

Would $x = x+1$ have infinite solutions?

1 vote

Is it OK if a proposition contains $\frac{1}{0}$?

1 vote
Accepted

Homology of a solid torus with a circle removed

1 vote

Is the square of a vector bundle trivial?