(1)(-3x²y²)²(2xy)³÷(xy)²
x-y/x²÷x²-2xy+y²/xy*(xy-x²)
-2y³+(3xy²-x²y)-2(xy²-y³)
3x²y+xy²-[2xy²-4x²y+(x²y-2xy²)
计算:(-7x²y)(2x²y-3xy³+xy)
计算;(xy-x²)÷x²-2xy+y²/xy · x-y/x²
计算[5xy²(x²-3xy)-(-3x²y²)³]÷(-5xy)
计算 2xy[4x²y²-3y(xy+x²y)-xy²]
(1)-2分之1xy(3y²-2xy+3x²y)
(1/2x²y-2xy+y²)×3xy
化简求值:【4(xy-1)²-(xy+2)(2-xy)】÷¼xy,其中x=-3,y=1/5
计算:(xy-x²)乘 x-y分之xy
(-2/3X³y+4x²y²-1/2xy²)/(-xy/4) 急