1) x + 2xy = x + 2xy = x(x-y)+2xy =
x-y x²-2xy+y² x-y (x-y)² (x-y)²
=x²-xy+2xy = x² +xy = x(x+y)
(x-y)² (x-y)² (x-y)²
2) 4xy - x - y = 4xy -x(x+y) -y(x+y) = 4xy -x²-xy-xy-y² =
x+y x+y x+y
=2xy-x² -y² = -(x² -2xy +y²) = -(x-y)²
x+y x+y x+y
3) x(x+y) * -(x-y)² = -x
(x-y)² x+y
Ответ: -х.