-3x²×(三分之一xy-y²)-10x(x²y-xy²)
x-y/x²÷x²-2xy+y²/xy*(xy-x²)
计算:(xy-x²)×x-y/xy
计算:(xy-x²)乘 x-y分之xy
3x²y+xy²-[2xy²-4x²y+(x²y-2xy²)
x²/xy-x/y
化简求值:(负三分之一 xy)²[xy(2x-y)-2x(xy-y²)],其中x=-一又二分之一,y
已知xy=1,求代数式负三分之一x(xy²+y+x³y四次方)的值
分式(x²-y²\xy)-(xy-y²\xy-x²)可化简为
(x+y)(x²-xy+y²)—xy(x+y)因式分解
(xy-x²)²÷(x-y)²/xy·x-y/x² 计算
计算 2xy[4x²y²-3y(xy+x²y)-xy²]
化简(3X²-XY+Y²)-5(X²-XY+2Y²)