已知2^x=3^y=6^z,xyz不等于0,求证:(1/x)+(1/y)+(1/z)=0……
已知2^x=3^y=6^z,xyz不等于0,求证:(1/x)+(1/y)+(1/z)=0……
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
已知x^2+y^2+z^2=1,求证x+y+z-2xyz
已知x+y+z=0,xyz=1,求证:x,y,z中必有一个大于2/3.
若1/2x=1/3y=1/4z且xyz不等于0,求x:y:z
1:已知4x-3y-6z=0 x+2y-7z=0且xyz不等于0
已知4x-3y+z=0,x+2y-8z=0,xyz不等于0,求x+y-z/x-y+2z的值
已知:(x+y)/z=(x+z)/y=(z+y)/x,且xyz不等于0,则分式(x+y)(x+z)(z+x)/xyz的值
已知xyz满足|3x-2y+z|+|2x+y+2z|=0(xyz不等于o)求x+y除以z
已知xyz属于R+,x+y+z=1,求证x^3/(y(1-y))+y^3/(z(1-z))+z^3/(x(1-x))大于