急x^2-3xy+2y^2+x^2+x-2m^2+n^2）x^2+m^2+n^2+mn

x³-xy²/x³+2x²y+xy² 与x²-y²/x(x+3y)+y(y-x) 急、、、、 (3x-y)^2+(2x+3y)(-2x-3y)+5xy 计算急 约分x^3-2x^2y/x^2y-2xy^2急 因式分解:12xy^2(y-x)+xy^3(x-y)+4x^2y(x-y) 计算：4xy²-3x²y-{3x²y-[2xy²-4x²y+2(x²y-2xy²)]急 x^2+xy/(x+y)^2如何约分急,快 (x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)答案应为-2x-x*x-3x， （x^2+xy/x-y)/（xy/x-y)计算 -xy^2(x+y)^3+x(x+y)^2因式分解 (x+3y)/(x^2+xy)-x+y计算题 (x^3+y^3)(x+y)变成（x+y）^2 *(x^2-xy+y^2)急求(x+y)(x^3+y^3)=(x+y)^2(x^2-xy+y^2) 因式分解 x-xy+3y-3x 2x+xy-y-4x+5y-6 【急】因式分解2x²-3xy-y² （x+y-2)(x+y-2xy)+(xy-1)² 这个怎么因式分解呀.急 急 急 急 急 [x(x^2y^2-xy)-y(x^2-x^3y)]/(2x^2y) [x(x^2y^2-xy)-y(x^2-x^3y)]/3x^2y [x(x^2y^2-xy)-y(x^2-x^3y)]/3x^2y 已知/X-Y-1/+(XY+3)的平方=0,求(-2XY+2X+3Y)-(3XY+2Y-2X)-(X+4Y+XY)的值!已知/X-Y-1/+(XY+3)的平方=0,求(-2XY+2X+3Y)-(3XY+2Y-2X)-(X+4Y+XY)的值急!