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NumberFour
  • Member for 12 years, 11 months
  • Last seen more than 5 years ago
  • Prague, Czech Republic
17 votes
4 answers
34k views

Some way to integrate $\sin(x^2)$? [duplicate]

16 votes
2 answers
3k views

Why is differential calculus built on open sets?

8 votes
1 answer
1k views

Group structure of an elliptic curve

4 votes
1 answer
1k views

Proving that if $n\times n$ Hadamard matrix exists, then 4 divides $n$

4 votes
4 answers
11k views

Eigenvectors of a normal matrix

4 votes
1 answer
7k views

Division of two random variables of uniform distributions

4 votes
2 answers
5k views

Eigenvectors of inverse complex matrix

3 votes
1 answer
181 views

Basic concepts in finite fields

3 votes
1 answer
1k views

Existence of total derivative of a function

3 votes
0 answers
115 views

Find extension of $\mathbb{Q}$ containing components of eigenvectors of a matrix

3 votes
1 answer
309 views

Find primitive element of splitting field of $1 + x + x^2 - x^5$

3 votes
2 answers
993 views

Question about kernel of reduction mapping of elliptic curves

3 votes
1 answer
111 views

Proof that $n+1$ divides $\sum_{k=1}^n k^q$ for $q > 0$

2 votes
1 answer
256 views

Determining parity of the multiplicative inverse?

2 votes
1 answer
396 views

Proof that limit goes to zero without Riemann-Lebesgue lemma

2 votes
4 answers
2k views

Calculate area under a curve

2 votes
2 answers
2k views

Series rearrangement and Riemann's theorem

2 votes
1 answer
616 views

Diagonalising quadratic form

1 vote
1 answer
845 views

Transformation of probability density function

1 vote
2 answers
162 views

Verification of normality of linear operator

1 vote
2 answers
65 views

Find $A^{-1}$(W) of linear manifold W

1 vote
2 answers
1k views

Emptiness and infiniteness decidable for recursive languages?

1 vote
1 answer
231 views

$B$-powersmooth number divides $\mathrm{lcm}(1,2,3,\ldots B)$

1 vote
2 answers
121 views

Is torsion subgroup of elliptic curve birationally invariant?

0 votes
2 answers
28 views

If $c \not\equiv 0 \pmod p$ then $\forall a \not\equiv 0\ \exists b \not\equiv 1$ so $c+a\equiv ab \pmod p$

0 votes
1 answer
191 views

Kernel of linear combination of functionals

0 votes
2 answers
1k views

When convergence in mean implies uniform convergence?

0 votes
1 answer
541 views

Points from an affine subspace with equal distance from given points

0 votes
1 answer
170 views

Convergence of random variable to a negative constant