3(2x^2y-xy^2)-(4xy^2+3x^2y)其中x=-1y=2

分类: 作业答案 • 2022-01-23 22:28:04

问题描述：

答

解由3(2x^2y-xy^2)-(4xy^2+3x^2y)
=6x^2y-3xy^2-4xy^2-3x^2y
=6x^2y-3x^2y-3xy^2-4xy^2
=3x^2y-7xy^2
=3（-1）^2×2-7（-1）×2^2
=6+28
=34