【xy(x²-3y)+3xy²】(-2xy)+x³y²(2x-y)
先化简,再求值:{xy(x²-3y)+3xy²}(-2xy)+x³y²(2x-y
3x²y+xy²-[2xy²-4x²y+(x²y-2xy²)
(2x²y-3xy²)-3(x²y-2xy²)+2(x²y-4xy
-2y³+(3xy²-x²y)-2(xy²-y³)
x²-2xy+y²分之x²+2xy-3y³如何因式分解
计算:(-7x²y)(2x²y-3xy³+xy)
x-y/x²÷x²-2xy+y²/xy*(xy-x²)
-3(xy-2x²)-[y²-(5xy-4x²)+2xy]
已知x:y=3:2,求(x²+3xy)/(xy+2xy)
计算:(xy-x²)×x-y/xy
计算 2xy[4x²y²-3y(xy+x²y)-xy²]
化简4xy-3y²-3x²+xy-3xy-2x²+x²-2y²