1. ## Factorise

Factorise completely
x^3-16x

2. Hello Mist
Originally Posted by Mist
Factorise completely
x^3-16x
Take out a common factor, $x$, and then use 'difference of two squares' on what's left in the bracket; i.e. $a^2 - b^2 = (a+b)(a-b)$.

Can you do it now?