(ab-4) (ab+4ab+16) упростите многочлен

Question

(ab-4) (ab+4ab+16) упростите многочлен

Answer 1

(ab-4)(ab+4ab+16)=(ab-4)(5ab+16)

Answer 2

(ab-4) (ab+4ab+16)=(ab-4)(5ab+16)=5a2b2+16ab-20ab-64=5a2b2-4ab-64