(x+y)³-(x-y)²(x+y)

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(x+y)³-(x-y)²(x+y)

(x+y)³-(x-y)²(x+y)
(x+y)³-(x-y)²(x+y)

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

(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)
=(x+y)2x*2y
=4xy(x+y)

(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)]
=(x+y)(x+y+x-y)(x+y-x+y)
=4xy(x+y)