1. ## Binomial Theorem

How would i use the binomial theorem to expand
(x+a)^4

2. Binomial Expansion

$\displaystyle (x+y)^n=\sum_{k=0}^n{n \choose k}x^{n-k}y^{k}\quad\quad\quad(1)$

Applying

$\displaystyle (x+a)^4=x^4+4x^3a+6x^2a^2+4xa^3+a^4$