[x(x³y²)²-2(x²y)³+3](xy²)³
[x(x²y²-xy)-y(x²-x³y)]÷3x²y
因式分解:[x(x²y²-xy)-y(x²-x³y)]÷3x²y
计算:(-7x²y)(2x²y-3xy³+xy)
-2y³+(3xy²-x²y)-2(xy²-y³)
计算(2x³-3x²y-2xy²)-(x³-2xy²+y³)
(2x³- 3x²y -2xy²)-(x³- 2xy²+y³
计算:x²y-(2xy²-5x²y)+3xy²-y³
x-y/x²÷x²-2xy+y²/xy*(xy-x²)
计算:x•(9x³y-3xy²)/(-3x²y)
计算[xy(x²-3y)+3xy²]·(-2xy)+x³y²(2x-y)
无论x,y取何值时,代数式:(x³+3x²y-5xy+6y³)+(y³+2xy&
[-xy/(x-y)²]²×(y²-xy/x)³