x+y+z=0,求x(1/y+1/z)+y(1/x+1/z)+z(1/x+1/y)+3

已知 x/(y+z)+y/(z+x)+z/(x+y)=1求 (x*x)/(y+z)+(y*y)/(x+z)+(z*z)/(x+y)=? 若|x+3|+|y-2|+|2×z+1|=0求(x×z-y×z)(y-x+z)的值 2|X-Y|+√2Y+Z+Z²-Z+1/4=0求X+Y+Z的值 XYZ(X+Y+Z)=1 求（x+y)(x+z)的最小值（X>0,Y>0,Z>O) x+y+z=1,且1/x+ 1/y 1/z=0,求x^+y^+z^ x+y=1 y+z=-1 z+x=0求x y z的值 已知｛2x-y-z=0,3x-9y+z=0求1,x:y:z 已知4x-3y-3z=0 x-3y-z=0 (1)求x:y:z 已知（1）X-Y+Z=0 (2)X+2Y-3Z=0 求X:Y:Z x+y=3,x+z=-1,y+z=0 解三元一次方程 求x,y,z x^2+y^2+z^2+4x+4y+4z+1=0,求x+y+z x^2+y^2+z^2+4x+4y+4z+1=0求x+y+z x^2+y^2+z^2+4x+4y+4z+1=0 求x+y+z 若实数XYZ满足2|x-y|+√2y+z+z方-z+1//4=0 求X+Y+Z 2y+z在根号里 X/Y+Z=Y/X+Z+1=Z/X+Y-1=X+Y+Z,求x+y+z等于多少 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 已知1/x+1/y+1/z=0,求x(1/y+1/z)+y(1/x+1/z)+z(1/x+1/y)的值.