Question

利用提公因式法因式分解（要详细步骤）

(x+y)^3-(x-y)^2(x+y)

Answer 1

(x+y)³-(x-y)²(x+y)
=(x+y)[(x+y)²-(x-y)²]
=(x+y)[(x+y)+(x-y)][(x+y)-(x-y)]
=4xy(x+y)

Answer 2

(x+y)^3-(x-y)^2(x+y)

=(x+y)[(x+y)^2-(x-y)^2]
=(x+y)(x+y+x-y)(x+y-x+y)
=4xy(x+y)

追问

[(x y)^2-(x-y)^2]怎样变成(x y x-y)(x y-x y)
呢

追答

平方差

追问

明白啦