计算：(x-y)(x²+xy+y²)

计算：(x-y)(x²+xy+y²)
计算：(x-y)(x²+xy+y²)

计算：(x-y)(x²+xy+y²)
原式＝x⑶+x²y+xy²-x²y-xy²-y⑶
=x⑶-y⑶

=a的三次方减b的三次方

(x-y)(x²+xy+y²)=x3-y3

(x-y)(x²+xy+y²)=x^3-y^3