(2x²y-2xy²)-[(-3x²y²+3x²y)+(3x²
急![(3x+y)²-3(3x-y)(x+y)-(x-3y)(x+3y)]÷(2xy)
计算3x[xy-2x(1/y-x/3]+3y(x²-y²)
3x²y+xy²-[2xy²-4x²y+(x²y-2xy²)
2x²-3xy=y²=0(x,y不得o)求x/y+y/x
化简 (x+y)(x²-xy+y²) ; 3(2x-1)(x+6)-5(x-3)(x+6)
x-y/x²÷x²-2xy+y²/xy*(xy-x²)
因式分解 (3x+2y)-(x-y)² x²-xy+3y-3x 2x²+xy-y²
(2x²y-2xy²)-[(-3x²y²+3x²y)+(3x²
(2x²y-3xy²)-3(x²y-2xy²)+2(x²y-4xy
(x+3y)(x-y)-(x+y)^2 =x²-xy+3xy-3y²-x²-y²
先化简,再求值:{xy(x²-3y)+3xy²}(-2xy)+x³y²(2x-y
[x(x²y²-xy)-y(x²-x³y)]÷3x²y