Question

Factorise the following:

(x² – 4)² – 9x²

Answer 1

Given: (x² – 4)² – 9x²

We know that,

(a + b) (a – b) = a² – b²

Hence,

⇒ (x² – 4)² – (3x)²

⇒ (x² – 4 + 3x) (x² – 4 – 3x)