Question

(3a^2- 8b^2) (3a^a- 8b^2)

Answer 1

$\rm ({3a}^2 - {8b}^2)({3a}^2 - {8b}^2) \\ \rm \mapsto {3a}^2 ({3a}^2 - {8b}^2) -{8b}^2 ({3a}^2 - {8b}^2) \\ \mapsto \boxed{ \rm{{9a}^4 - {24b}^2 a^2 - {24b}^2 a^2 + {64b}^4 }}$