先化简再求值 [2x（x^2y-xy^2）+xy(xy-x^2)]÷x^2y 其中=x2008 y=2004_数学解答

先化简再求值 [2x（x^2y-xy^2）+xy(xy-x^2)]÷x^2y 其中=x2008 y=2004

人气：159 ℃　时间：2019-08-19 04:46:06

解答

[2x（x^2y-xy^2）+xy(xy-x^2)]÷x^2y
=(2x^3y-2x^2y^2+x^2y^2-x^3y)÷x^2y
=(x^3y-x^2y^2)÷x^2y
=x-y
=2008-2004
=4