因式分解(7) 送分

1.
x3(2x - y) + xy(2x - y)2
= x(2x - y)[x2 + y(2x - y)]
= x(2x - y)(x2 + 2xy - y2)

2.
(x - 2y)2 - 3x(x - 2y)
=(x - 2y)[(x - 2y) - 3x]
= (x - 2y)(-2x - 2y)
= -2(x - 2y)(x + y)
或 2(2y - x)(x + y)

3.
x3(2x - y) - xy(2x - y)2
= x(2x - y)[x2 - y(2x - y)]
= x(2x - y)(x2 - 2xy + y2)
= x(2x - y)(x - y)2

4.
2x2(x + y) - y(x + y)2
= (x + y)[2x2 - y(x + y)]
= (x + y)(2x2 - xy - y2)
= (x + y)(2x + y)(x - y)

5.
3x(x - 2y)2 - (x - 2y)3
= (x - 2y)2[3x - (x - 2y)]
= (x - 2y)2(3x - x + 2y)
= (x - 2y)2(2x + 2y)
= 2(x - 2y)2(x + y)

6.
2x2(x + 1)2 - 12x(x + 1)
= 2x(x + 1)[x(x + 1) - 6]
= 2x(x + 1)(x2 + x - 6)
= 2x(x + 1)(x + 3)(x - 2)
=