先化简,再求值;(x^2y-x^3)\(x^2+2xy+y^2)÷x\(x-y)×(x+y)\(x^2-2xy+y^2),已知x=_数学解答

先化简,再求值;(x^2y-x^3)\(x^2+2xy+y^2)÷x\(x-y)×(x+y)\(x^2-2xy+y^2),已知x=1\3,y=-2\3

人气：197 ℃　时间：2020-01-27 18:51:30

解答

(x^2y-x^3)/(x^2+2xy+y^2)÷x/(x-y)×(x+y)/(x^2-2xy+y^2)=x^2(y-x)/(x+y)^2÷x/(x-y)×(x+y)/(x-y)^2=x^2(y-x)/(x+y)^2×(x-y)/x×(x+y)/(x-y)^2=x(y-x)/(x+y)×1/(x-y)=-x(x-y)/(x+y)×1/(x-y)=-x/(x+y)=(-1/3)/(1...