x+y=1 y+z=-1 z+x=0求x y z的值

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 XYZ(X+Y+Z)=1 求（x+y)(x+z)的最小值（X>0,Y>0,Z>O) 2|X-Y|+√2Y+Z+Z²-Z+1/4=0求X+Y+Z的值 已知 (x+y-z)/z=(x-y+z)/y=(y+z-x)/x,且xyz≠0,求代数式 ((x+y)(y+z)(x+z))/xyz x分之y+z=y分之z+x=z分之x+y(x+y+z不等于0）,求x+y+z分之x+y-z 分式加减法：已知x+y/z=x+z/y=y+z/x(x+y+z≠0）,求x+y-z/x+y+z 已知x+y/z=x+z/y=y+z/x(x+y+z≠0）,求x+y-z/x+y+z的步骤 已知x+y/z=x+z/y=y+z/x(x+y+z≠0）,求x+y-z/x+y+z的步骤 已知：x^2/(z+y)+y^2/(x+z)+z^2/(x+y)=0,求x/(z+y)+y/(x+z)+z/(x+y)的值. x^2/(z+y)+y^2/(x+z)+z^2/(x+y)=0,求x/(z+y)+y/(x+z)+z/(x+y)的值 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 (y+z)/x=(z+x)/y=(x+y)/z求x+y-z/x+y+z的值 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 x+y=3,x+z=-1,y+z=0 解三元一次方程 求x,y,z