Question

помогите пожалуйста разобраться​

Answer 1

1) ${(a + 7)}^{2} = {a}^{2} + 2 \times a \times 7 + {7}^{2} = {a}^{2} + 14a + 49$

2) $(m - 6)(m + 6) = {m}^{2} + 6m - 6m - 36 = {m}^{2} - 36$

3) ${(3x - 4y)}^{2} = {(3x)}^{2} - 2 \times 3x \times 4y + {(4y)}^{2} = 9 {x}^{2} - 24xy + 16 {y}^{2}$

4) $(y + 1)( {y}^{2} - y + 1) = {y}^{3} - {y}^{2} + y + {y}^{2} - y + 1 = {y}^{3} + 1$