约分(x²y+xy²)/(xy³-x³y)

[-xy/(x-y)²]²×(y²-xy/x)³ 约分：2x²y-2xy²/x²-2xy+y² 约分 （6ab²)/(8b³) (x³-2x²y)/(x²y-2xy& 计算：(xy-x²)×x-y/xy 约分：x²+y²-9-2xy/x²-y²+6x+9 (3xy)² · (x²+xy-y²)-3xy(3x³y+3x²y&# 先化简,再求值:{xy(x²-3y)+3xy²}(-2xy)+x³y²(2x-y x²/xy-x/y -x³y³-x²y²+xy x³y-2x²y²+xy³ 约分a²-ab+b²/a³+b³ x²-xy-2y²/x&# 分式约分：x²-4y²/x²+2xy+y²