Question

(A+b)(a-b)+(a-b)(a2+ab+b2)

Answer 1

= {(a+b)(a-b)} + {(a-b) (a2+ab+b2)}
= (a2-b2) + a(a2+ab+b2) - b(a2+ab+b2)
= (a2-b2) + a3+ a2b+ab2-a2b-ab2-b3
= a3-b3+a2-b2