(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)
(2x²y-3xy²)-3(x²y-2xy²)+2(x²y-4xy
2x²-3xy=y²=0(x,y不得o)求x/y+y/x
(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
先化简在求值(x+y)²-(x-y)(x+y)-(xy)²÷(xy),其中x,y是方程组『3x+2y
x²/xy-x/y
化简 (x+y)(x²-xy+y²) ; 3(2x-1)(x+6)-5(x-3)(x+6)
(x-y)²-(3x-3xy+y²)因式分解
因式分解 (3x+2y)-(x-y)² x²-xy+3y-3x 2x²+xy-y²