若x:y=2:3,y:z=1:2,且x+y+z=55,则y=?
若x + 1/y =y + 1/z =z + 1/x,且x,y,z互不相等,则x^2y^2z^2=( )
已知 x,y,z都是正实数,且 x+y+z=xyz 证明 (y+x)/z+(y+z)/x+(z+x)/y≥2(1/x+1
x,y,z为实数 且(y-z)^2+(x-y)^2+(z-x)^2=(y+z-2x)^2+(x+z-2y)^2+(x+y
x,y,z为实数且(y-z)平方+(x-y)平方+(z-x)平方=(y+z-2x)平方+(z+x-2y)平方+(x+y-
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
若2分之x+y=3分之y+z=5分之x+z 且x+y+z=18 求x,y,z的值
已知方程组4x-y+3z=0 2x+y+6z=0且xyz不等于0,则x/y+y/z+z/x是多少
已知x,y,z都是正数,且xyz=1,求证:x^2/(y+z)+y^2/(x+z)+z^2/(x+y)≥3/2
若x-2y+4z=1,x+3y-7z=0,则y:z=?
若x,y,z属于R+,且x+2y+3z=36,则1/x+2/y+3/z的最小值是________.
若x,y,z均为实数,且(x-1)²+|y+2|+根号(z-3)²=0则x,y,z的值分别为?
已知x:y:z=2:3:4,且x-y+z=36,求x+y+z的值.