Question

Помогите пожалуйста

Answer 1

1.

$- 2x {y}^{2} (2y - 3x + {x}^{2} ) = - 4x {y}^{3} + 6 {x}^{2} {y}^{2} - 2 {x}^{3} {y}^{2}$

$3xy(2x - 3 {x}^{2} + 4xy) = 6 {x}^{2} y - 9 {x}^{3}y + 12 {x}^{2} {y}^{2}$

2.

$4( {x}^{2} - 3x + 2) - 2(2 {x}^{2} - 5x + 1) = 4 {x}^{2} - 12x + 8 - 4 {x}^{2} + 10x - 2$

4х²-12х+8-4х²+10х-2

т.к х = -3 =>

36+36+8-36-30-2=12

Ответ 12.

3.

$2xy(x - y) - 3 {x}^{2} (x + {y}^{2} ) = 2 {x}^{2} y - 2x {y}^{2} - 3 {x}^{3} - 3 {x}^{2} {y}^{2}$