因为 (2x-1)^2+|y+2|=0
所以 2x-1=0 y+2=0
x=1/2 y=-2
3x^2 y+2xy^2+2(xy-2x^2y)-xy+3xy^2
=3x^2y+2xy^2+2xy-4x^2y-xy+3xy^2
=-x^2y+5xy^2+xy
=-(1/2)^2*(-2)+5*(1/2)*(-2)^2+1/2*(-2)
=1/2+5/2-1
=3-1
=2
因为 (2x-1)^2+|y+2|=0
所以 2x-1=0 y+2=0
x=1/2 y=-2
3x^2 y+2xy^2+2(xy-2x^2y)-xy+3xy^2
=3x^2y+2xy^2+2xy-4x^2y-xy+3xy^2
=-x^2y+5xy^2+xy
=-(1/2)^2*(-2)+5*(1/2)*(-2)^2+1/2*(-2)
=1/2+5/2-1
=3-1
=2