先化简,再求值x-2(1/4x-1/3y^2)+(-3/2x+1/3y^2),其中x=3/2,y=-2

问题描述:

先化简,再求值x-2(1/4x-1/3y^2)+(-3/2x+1/3y^2),其中x=3/2,y=-2

x-2(1/4x-1/3y^2)+(-3/2x+1/3y^2)
=x-1/2x+2/3y^2-3/2x+1/3y^2
=-x+y^2
x=3/2,y=-2
那么
原式=-3/2+(-2)^2=-3/2+4=5/2=2.5