User Diego Robayo - Mathematics Educators Stack Exchange

Diego Robayo

Member for 8 years, 11 months
Last seen more than 8 years ago

Bogotá-Colombia

Network profile

Stats

101

reputation

0

reached

0

answers

0

questions

Communities

About

Math Student at "Universidad de los Andes" in Colombia.

Badges

This user doesn’t have any gold badges yet.

This user doesn’t have any silver badges yet.

1

bronze badge

Autobiographer

Dec 23, 2014

Posts

This user hasn’t posted yet.

Top network posts

View all network posts

12

Prove that $1 + 4 + 7 + · · · + 3n − 2 = \frac {n(3n − 1)}{2}$

5

Combinatorial proof of $n(n-1)2^{n-2} = \sum_{i=2}^{n}k(k-1)\binom{n}{k}$

5

Shortest and most elementary proof that the product of an $n$-column and an $n$-row has determinant $0$