Fully factorise

Question

16x^36 -1

Answer 1

16x^36 - 1
= (4x^18)^2 - 1^2
= (4x^18 - 1)(4x^18 + 1)
= ((2x^9)^2 - 1^2)(4x^18 + 1)
= (2x^9 - 1)(2x^9 + 1)(4x^18 + 1)