Rene Schipperus's user avatar
Rene Schipperus's user avatar
Rene Schipperus's user avatar
Rene Schipperus
  • Member for 9 years, 11 months
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20 votes
4 answers
837 views

Tripos Integral

12 votes
3 answers
682 views

$\frac1{12}(\sin^2A+\sin^2B+\sin^2C)\leq \sin^2\frac12B\sin^2\frac12C+\sin^2\frac12C\sin^2\frac12A+\sin^2\frac12A\sin^2\frac12B$ for $A+B+C=180^\circ$

11 votes
5 answers
960 views

Inequality for absolute values

11 votes
3 answers
582 views

Eliminating $\theta$ from $x=\cos\theta(2-\cos 2\theta)$ and $y=\sin\theta(2-\sin 2\theta)$

10 votes
5 answers
655 views

Five Porismatic Equations.

8 votes
1 answer
400 views

Example of non quasi-compact scheme.

8 votes
2 answers
244 views

Eliminate ${\theta, \varphi}$ from $\tan\theta+\tan\varphi=a$, $\sec\theta+\sec\varphi=b$, $\csc\theta+\csc\varphi=c$

6 votes
0 answers
994 views

Leray's theorem for cech and derived sheaf cohomology.

6 votes
2 answers
89 views

Eliminating $x$, $y$, $z$ from $\frac{x^2-xy-xz}{a}=\frac{y^2-yx-yz}{b}=\frac{z^2-zx-zy}{c}$ and $ax+by+cz=0$

5 votes
2 answers
119 views

Determinant Identity: Elegant Solution Please.

5 votes
1 answer
173 views

Limit of Recursive Sequence $y_{n+1}=y_n+\frac{1}{ny_n}$ with $y_1=1$

5 votes
1 answer
592 views

$27$ lines on a cubic with multiplicity. Contradiction?

5 votes
1 answer
706 views

Abelian Kummer Extension

5 votes
1 answer
521 views

Formula for distance between Incenter and Orthocenter.

5 votes
4 answers
333 views

Calculate Indefinite Integral $\int \frac{x^5(1-x^6)}{(1+x)^{18}}dx$

4 votes
3 answers
386 views

$\int_0^{\frac{\pi}{2}}\ln(\sin^2 x+k^2\cos^2 x)dx$ not by differentiation under the integral?

4 votes
5 answers
270 views

Prove that the function $\frac{e^x-1-x}{x^2}$ is increasing.

4 votes
0 answers
138 views

Resultants of two polynomials over a ring

4 votes
4 answers
305 views

Eliminating $\theta$ from $\cos^3\theta +a\cos\theta =b$ and $\sin^3\theta +a\sin\theta =c$

3 votes
2 answers
370 views

Construct the angle whose sine is $\frac{3}{2+\sqrt{5}}$

3 votes
3 answers
120 views

Tripos Type Integral

3 votes
3 answers
189 views

Integral of Euler.

3 votes
4 answers
345 views

Limits in complex plane.

3 votes
2 answers
3k views

Differentiability of multivariate functions.

3 votes
1 answer
125 views

Chain Rule Puzzle

3 votes
2 answers
262 views

Eliminate $\theta$ from $4x=5\cos\theta -\cos 5\theta$ and $4y=5\sin\theta -\sin 5\theta$

3 votes
1 answer
150 views

Proving $\pi^2=18\sum_{n=0}^{\infty}\frac{n!n!}{(2n+2)!}$

2 votes
1 answer
350 views

Continuity conditions for multivariate functions.

2 votes
0 answers
117 views

A problem in elementary combinatorial space geometry.

2 votes
1 answer
128 views

Eliminating $r$ from $6\tan(r+x)=3\tan(r+y)=2\tan(r+z)$