[x(x²y²-xy)-2y(x²-x³y)÷3x²y

急![(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)]÷(2xy) x²/xy-x/y [x（x²y²-xy）-y（x²-x³y）]÷3x²y 【x(x²y²-xy)-y(x²-x³y)】÷3x²y 因式分解：[x（x²y²-xy）-y（x²-x³y）]÷3x²y 化简x-y分之x + x³-2x²y+xy²分之y³ ÷ y²-x&# x-y/x²÷x²-2xy+y²/xy*（xy-x²） 【(1)/(x-y)+(1)/(x-y)】÷(2x)/(x²-2xy+y²) 计算3x[xy-2x(1/y-x/3]+3y(x²-y²) x³y-2x²y²+xy³ [-xy/(x-y)²]²×(y²-xy/x)³ 化简：[(x+y)²-(x-y)²]÷2xy