1-x²+2xy-y²
1-x²+2xy-y²
计算:(1).(-2xy²)*(3x²y)²
(x+y-2xy)(x+y-2)+(1-xy)²
x²-4y²/x²+2xy+y²÷x+2y/2x²+2xy
方程组{x²+y²=10(1)x²-3xy+2y²=0(2)怎么解
x³y³-x²y²-xy+1
越快越好(1)(xy²+3)(xy²+3)-2x(-x+y)(2)(x+2)(x²+4)(
先化简,再求值:3xy²(-x²y+2x³y²)-4xy(-xy²)·
因式分解 x²-3xy+2y²+x-2
(x+2y)²-x²-2xy
已知|x+2|+(y+1²=0,求x²+(2xy-3y²)-2(x²+xy-2y
已知x/y=1/2,则x²-3xy+2y²/2x²-3xy+7y²