Question

分解因式：[(ab+1)(ab-2)-2a^2b^2+2]除以（-ab)

Answer 1

[(ab+1)(ab-2)-2a^2b^2+2]/（-ab)

=[(ab)^2-ab-2-2(ab)^2+2]/ab

=[-(ab)^2-ab]/(-ab)

=-[ab(ab+1)]/(-ab)

=ab+1.