Question

Factorise
(x + 2)³ – (x – 2)³

Answer 1

(x + 2)³ – (x – 2)^{3
$$\begin{gathered} =\left(x+2-x+2\right)\left[{\left(x+2\right)}^2+{\left(x-2\right)}^2+\left(x^2-4\right)\right] \\ =4\left[x^2+4+4x+x^2+4-4x+x^2-4\right] \\ =4\left(3x^2+4\right) \end{gathered}$$}