User Carlos Eugenio Thompson Pinzón - Mathematics Stack Exchange

Carlos Eugenio Thompson Pinzón

Member for 10 years, 2 months
Last seen more than a month ago

blog.chlewey.net
Bogotá

78 Answers

Score Activity Newest

26 votes

Is zero a prime number?

answered Oct 25, 2013 at 17:33

14 votes

Accepted

Total number of divisors is a prime

answered Nov 4, 2013 at 11:50

12 votes

Accepted

What does this combination of symbols mean? $\exists !$

answered Dec 15, 2013 at 13:52

9 votes

Accepted

How to find the $f^{-1}(x)$ of $f(x)=x^{3}-12x+\frac{48}{x}-\frac{64}{x^{3}}$

answered Oct 16, 2013 at 13:17

8 votes

Accepted

Is the shadow of the earth coming up almost matching in size with the moon a coincidence?

answered Dec 7, 2013 at 13:46

4 votes

Accepted

Explicit Bijection from $\mathbb{N}$ to $\mathbb{Q}^+$.

answered Dec 11, 2013 at 0:53

4 votes

Find two sets $A$ and $B$ such that $A$ is an element of $B$ and $A \subseteq B$.

answered Dec 6, 2013 at 17:24

4 votes

Accepted

Deducing $\sin x + \cos x \ge 1$ from $(\sin x + \cos x)^2 = 1 + 2 \sin x \cos x$

answered Oct 13, 2013 at 3:32

4 votes

Accepted

Prove this limit as $x\to\infty$

answered Oct 21, 2013 at 5:12

3 votes

Accepted

Ruler and compass construction of the unit-distance petersen graph embedding

answered Nov 1, 2013 at 21:11

3 votes

Find the intersection of the surface $z=2x^2+y^2$ with the $x-y$ plane

answered Oct 18, 2013 at 19:16

3 votes

Let $f(x)$ be a 3rd degree polynomial such that $f(x^2)=0$ has exactly $4$ distinct real roots

answered Oct 21, 2013 at 3:22

3 votes

Proving that $\lim_{x\rightarrow a}f(x) = \lim_{h\rightarrow 0} f(a+h) $

answered Oct 21, 2013 at 4:07

3 votes

Accepted

derivative of a summation with variable upper limit

answered Oct 16, 2013 at 23:57

3 votes

Accepted

How to solve $(2x+2, 6x) = x+1$

answered Nov 7, 2013 at 2:02

3 votes

Accepted

Divide trapezoid into 4 equal parts.

answered Dec 4, 2013 at 19:40

3 votes

Accepted

Inequality in triangle involving medians

answered Dec 23, 2013 at 18:41

2 votes

Suppose $A,B,C$ are sets. Prove that $A\mathbin\triangle B\subseteq C \iff A\cup C=B\cup C$.

answered Dec 10, 2013 at 22:47

2 votes

Correct my proof that: $\tan^{-1}(1) + \tan^{-1}(2) +\tan^{-1}(3) = \pi$

answered Feb 3, 2017 at 16:39

2 votes

Accepted

Finite Continued Fraction Proof

answered Dec 4, 2013 at 20:26

2 votes

Accepted

showing that $c^{\frac{1}{n}}$ is increasing.

answered Oct 30, 2013 at 21:27

2 votes

Accepted

Integrating strips normal to the curve

answered Dec 6, 2013 at 20:57

2 votes

Which is the impossible voting in election?

answered Dec 7, 2013 at 17:14

2 votes

Getting $x,y$ position on an image based on given value

answered Dec 13, 2013 at 20:35

2 votes

name of rule that says: x(x+1) is even number

answered Nov 8, 2013 at 16:56

2 votes

Prove intersection of all inductive sets is inductive

answered Dec 4, 2013 at 13:13

2 votes

Accepted

Area of a circular segment.

answered Oct 16, 2013 at 19:30

2 votes

Proving $mn=nm$ for all $n,m\in \mathbb N$

answered Oct 13, 2013 at 4:26

2 votes

Critical point of a function

answered Oct 13, 2013 at 4:55

2 votes

I need some help on solving a recursive function question

answered Oct 13, 2013 at 14:05

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