My Favorite Proof Of The N Choose K Formula!

My favorite proof of the n choose k formula!

Proof: Recursive Identity for Binomial Coefficients | Combinatorics

Binomial Coefficient

The Bright Side of Mathematics

What is n choose k? || formula, examples, Pascal's triangles

Binomial Theorem, prove n choose k = n!/(k!(n-k)!)

Mathisyourfriend

Combinatorial proof that (n choose k)=(n-1 choose k)+(n-1 choose k-1)

The Combination Formula and Why it Works | Combinatorics, Combinations and Permutations

Sum of n CHOOSE k (Nice identity!)

What does n choose k mean?

Nikolay's Genetics Lessons

n Choose k Equals n Choose n-k

PageWizard Games, Learning & Entertainment

Combination formula | Probability and combinatorics | Probability and Statistics | Khan Academy

Combinatorial Proof that (n choose k)(k choose l)=(n choose l)(n-l choose k-l)

Why is n choose k Involved in Binomial Expansion?

N Choose K Derivation

Left As An Exercise for the Reader

Prove that Sum(n choose r) = 2^n

The Math Sorcerer

n choose 2 choose 2

Binomial Coefficients -- Proof Writing 7

Proving by induction that $ sum_{k=0}^n{n choose k} = 2^n$ (4 Solutions!!)

Roel Van de Paar

Combinatorial Results: N choose k

Derive the Combinations Formula

David Dobervich