(x-y)方×(x方+xy+y方)—(x立方+y立方)×(-x立方+y立方)

问题描述:

(x-y)方×(x方+xy+y方)—(x立方+y立方)×(-x立方+y立方)

(x-y)方×(x方+xy+y方)—(x立方+y立方)×(-x立方+y立方)
=(x-y)×(x-y)×(x方+xy+y方)+(x立方+y立方)×(x立方-y立方)
=(x立方-y立方)【(x-y)+(x立方+y立方)】