计算(x-y)(x平方+xy+y平方)-(x+y)(x平方-xy+y平方)

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计算(x-y)(x平方+xy+y平方)-(x+y)(x平方-xy+y平方)

计算(x-y)(x平方+xy+y平方)-(x+y)(x平方-xy+y平方)
计算(x-y)(x平方+xy+y平方)-(x+y)(x平方-xy+y平方)

计算(x-y)(x平方+xy+y平方)-(x+y)(x平方-xy+y平方)
=x^3-y^3-(x^3+y^3)
=-2y^3
^3表示三次方

直接展开化简就可以啊
=4xy^2-4y^3
就是4XY平方-4Y三次方

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