解[x(x²y²-xy)-y(x²+x³y)]÷4x²y=(x³y²-x²y-x²y-x³y²)÷4x²y=(-2x²y)÷4x²y=-1/2第一道是这样吗8x(1/2x²)-6x(1/3x²+2/3)8x(1/2x²-1)-6x(1/3x²+2/3)8x(1/2x²-1)-6x(1/3x²+2/3)=4x³-8x-2x³-4x=2x³-12x