Question

Factorise:

`a^3 + 1/(27a^3)`

Answer 1

Given expression: `a^3 + 1/(27a^3)`

⇒ `a^3 + (1/(3a))^3`

We know that,

a³ + b³ = (a + b) (a² – ab + b²)

Hence,

`(a + 1/(3a)) (a^2 - 1/3 + 1/(9a^2))`