y=(x+2)/(x^2+3x+6)的值域是?急用,谢谢!

若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 当2x-y/x+y=3时,求代数式2x-y/2x+2y+x+y/6x-3y的值. 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 x,y 满足x(x-2)-y(y-6)=-10,求x,y的值 y=3(x-y),x=2(x-y)求x,y的值 x*x+2x-y*y+6y-8=0,x+y不等于2,求x-y的值 化简求值：已知x、y满足：x^2+y^2-4x+6y+13=0 求代数式 的值.(3x+y)^2-3(3x-y)(x+y)-(x-3y)(x+3y)急用！ 把下列各式分解因式 x(x+y)(x-y)-x(y+x)² 2 已知2x+y=6,x-3y=1,求7y（x-3y）²把下列各式分解因式x(x+y)(x-y)-x(y+x)²7、已知2x+y=6,x-3y=1,求7y（x-3y）²-2（3y-x）³的值 已知x^2-y^2=6,x+y=3求x.y的值 1.(x-2y)(x+2y)-(x平方+y)(x平方-y) 2.(2x-y)(y+2x)-(2y+x)(2y-x)3.已知：x+y=6,x平方-y平方=48,求x,y的值4.x平方-2x分之x+2 -- x平方-4x+4分之x-1 若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值 x@y=(x+y)除以2,X#Y=3X-Y除以2 问：(9@x）#30=6,求x的值. x^2+4y^2-6x+4y+10=0,求x^4-y^4/(x+2y)(x-2y)*x+2y/xy^2+y^3除以（x^2+y^2/y)^2的值 已知4x²+y²-4x-6y+10=0求（2/3x（√9x）+(y²√x/y³)×(x²√1/x×5x√y/x)的值 已知4x²+y²-4x-6y+10=0求（2/3x（√9x）+(y²√x/y³)-(x²√1/x-5x√y/x)的值 已知4x²+y²-4x-6y+10=0,求[(2/3)x√(9x)+y²√(x/y³)-(x²√(1/x)-5x√(y/x)的值 已知x-y=1,求[(x+2y)^2+(2x+y)(x-4y)-3(x+y)(x-y)]除以y的值大神们帮帮忙 已知x-y=1,求[(x+2y)²+(2x+y)(x-4y)-3(x+y)(x-y)]÷y的值