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Damaru
  • Member for 9 years, 7 months
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8 votes
1 answer
495 views

Given a regular compact surface $S$ in $\mathbb{R}^3$ proof there exists a line in $\mathbb{R}^3$ which intersects perpendicularly with $S$ twice

6 votes
3 answers
1k views

Computationally efficient form to evaluate multivariate polynomials?

3 votes
2 answers
186 views

Why isn't this function $f:\mathbb N \to \mathcal P(\mathbb N)$ a surjection?

2 votes
1 answer
157 views

if $\sum_{n=1}^{\infty }a_{n}$ converges ($a_{n}$ are non negatives), study the convergence of the serie $\sum_{n=1}^{\infty }\sqrt{\frac{a_{n}}{n}}$

2 votes
2 answers
74 views

Is an holomorphic function injective if $\| f'(z)\| > 0 $?

2 votes
1 answer
430 views

Efficient way to compute the symmetric reduction of special polynomials (specially for resolvents)

2 votes
1 answer
8k views

Find the derivative of the inverse of this real function $f(x) = 2x + \cos(x)$

1 vote
0 answers
256 views

Example of a second countable space but not locally compact?

1 vote
0 answers
44 views

Is the set finite words over an alphabet a final coalgebra*?

1 vote
0 answers
55 views

Is there any method for gradient descent that achieves acceleration while moving always in the opposite direction of the gradient?

1 vote
1 answer
51 views

Build two homothetical figures with n and n +1 tiles all isometric pairwise

0 votes
0 answers
105 views

Show that $\sum_{n=1}^{\infty} \frac{z^n}{n}$ converges for $z \in \mathbb{C}$ such that $\|z\|=1$ but $z \neq 1$

0 votes
2 answers
2k views

Is $-\log (1-z) = \sum_{n=1}^{\infty}\frac{z^n}{n}$ for $z \in \mathbb{C}, \|z\|=1, z \neq 1$? [closed]

0 votes
3 answers
688 views

A diffeomorphism with negative Jacobian swaps the orientation?