Factoring a cube expression - (Step by step)

Question

How can I factor the following expression:

$$(a+3)^3$$

Please, step by step so I can learn.

Answer 1

As noted in the comments $(a+3)^3=(a+3)(a+3)(a+3)$ is already factored.

The expression in your comment is the factorization of a different binomial expression: $$ a^3+4^3=(a+4)(a^2-4a+4^2) $$

You can verify this identity simply multiplying the factors.