Question

Factorise.

24a³ + 81b³

Answer 1

24a³ + 81b³

3 (8a³ + 27b³)

3 ((2a³) + (3b)³)

we know that,

a³ + b³ = (a + b) (a² − ab + b²)

= 3 (2a + 3b) ((2a)² − 2a × 3b + (3b)²)

= 3 (2a + 3b) (4a² − 6ab + 9b²)