先化简在求值(-1/3XY)²×[xy(2x-y)-2x(xy-y)²],=1/9x²y²*(2x²y-xy²-2x²y+2xy²)=1/9x²y²*xy²=1/9x³y^4=1/9x(-3/2)³x(-2)^4=-1/9x27/8x16=-61/9x(-3/2)³x(-2)^4=-1/9x27/8x16 ??1/9=-1/9???(-3/2)³=-27/8呀，把负号放前面