xyz是正数且满足x+y-5z=0和x-y+z=0求(x^2-y^2)/(z^2-x^2)
若xyz不等于0,且满足(y+z)/x=(x+z)/y=(x+y)/z,求(y+z)(x+z)(x+y)/xyz的值
已知XYZ满足方程组 X+Y-Z=6 Y+Z-X=2 Z+X-y=0 求X Y Z的值
已知xyz不等于0,且x+2y-z=0,7x-y-z=0,求x+y+z/2x-y-z的值.
已知x+y-z/z=x-y+z/y=-x+y+z/x,且xyz不等于0,求分式[(x+y)(x+z)(y+z)]/xyz
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
已知xyz满足|3x-2y+z|+|2x+y+2z|=0(xyz不等于o)求x+y除以z
设xyz不 等于0,且2x-y+z=0,x+2y-5z=0,试求代数式(x-y)/(y+z) 的值
已知x+y-7z=0 x-2y+5z=0(xyz不等于0),求x+2y-z/y-2x+12z
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)
已知xyz满足方程组x+4y-3z=0,求x:y:z的值 4x-5y+2z=0
已知xyz满足x-2y+z=0 7x+4y-5z=0,求y+z分之x的值
设X+Y+Z=0求X^3+X^2Z-XYZ+Y^2Z+Y^3的值