2x³+2xy²-x(x²-2xy+y²)+x(x²+2xy+y²) = 2x³+2xy²-x³+2x²y-xy²+x³+2x²y+xy²= 4x³+2xy²+4x²y
x=-1.5
y=-0.5
4*(-1.5)³+2*(-1.5)*(-0.5)²+4*(-1.5)²(-0.5)=-13.5-0.75-4.5= 8.25
2x³+2xy²-x(x²-2xy+y²)+x(x²+2xy+y²) = 2x³+2xy²-x³+2x²y-xy²+x³+2x²y+xy²= 4x³+2xy²+4x²y
x=-1.5
y=-0.5
4*(-1.5)³+2*(-1.5)*(-0.5)²+4*(-1.5)²(-0.5)=-13.5-0.75-4.5= 8.25