证明:若z=x^y(x>0且x≠1),则(x/y)(αz/αx)+(1/ln x)(αz/αy)=2z
证明:若z=x^y(x>0且x≠1),则(x/y)(αz/αx)+(1/ln x)(αz/αy)=2z
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
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)
若x + 1/y =y + 1/z =z + 1/x,且x,y,z互不相等,则x^2y^2z^2=( )
若x,y,z是正实数,且x+y+z=xyz,证明:(y+z/x)+(z+x/y)+(x+y/z)≥2倍的(1/x)+(1
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
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
若xy-z不等于0,且(y+x)/x=(z+x)/y=(y+x)/z,求[(y+z)(z+x)(x+y)]/xyz的值?
(x+y-z)(x-y+z)=
已知(x+y+z)^2=x^2+y^2+z^2,证明x(y+z)+y(z+x)+z(x+y)=0
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
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