(x-y)的3次方-2(x-y)(y-x)的平方-3(x-y)的4次方除以(y-x)
问题描述:
(x-y)的3次方-2(x-y)(y-x)的平方-3(x-y)的4次方除以(y-x)
答
=(x-y)³-2(x-y)³+3(x-y)³
=2(x-y)³