Question

Coloque os cálculos por favor​

Answer 1

$(x - y) {}^{2} - (x + y) {}^{2} \\ ( - 2y) \times 2x \\ - 4xy$

$(3 + ab) \times (ab - 3) \\ (ab + 3) \times (ab - 3) \\ a {}^{2} b {}^{2} - 9$