6x^2y(x-y)-2xy^2(x-y)+8xy(y-x)

题目

6x^2y(x-y)-2xy^2(x-y)+8xy(y-x)
(x-y)^2-xy^2+x^2y
b^2-c^2+a^2-2ab

答案

1.=2xy(x-y)[3x-2y-4]
2.(x-y)^2-xy(y-x)=(x-y)(x-y+xy)
3.(a+b)^2-c^2=(a+b+c)(a+b-c)
这是作业,自己用点心比较好.