# Prove that the rᵗʰ term in the nᵗʰ row of Pascal's triangle is nCr.

Prove that the rᵗʰ term in the nᵗʰ row of Pascal's triangle is nCr.

nCr formula: n!/r!(n-r)!

I've tried everything I can but I don't know how to approach this question.

Have you tried induction?

You might try (x + y)^1 show that the coefficients are 1 and 1; and then assume it's true for (x+y)^n and show if that is true then it works for the row (x + y) ^(n+1).

I haven't tried that; but it would be my first try.

haruspex