xy/x+y=1 yz/y+z=2 xz/x+z=3 求xyz/x+y+z=?
已知x+y+z=3,xy+yz+xz=-1,xyz=2,求x^2y^2+y^2z^2+x^2z^2
xy/x+y=1 yz/y+z=2 xz/x+z=3 求xyz/x+y+z=?
x+y+z=1,x,y,z都是正数,求xy+yz+xz-3xyz的最大值和最小值
已知xyz=1,求x/(xy+x+1)+y/(yz+y+1)+z/(xz+z+1)的值
已知,xyz=0,求x/(xy+x+1)+y/(yz+y+1)+z/(xz+z+1)值?
设x,y,z∈R+,xy+yz+xz=1,证明不等式:(xy)^2/z+(xz)^2/y+(yz)^2/x+6xyz≥x
分式题:xy=x+y,yz=2(y+z),zx=3(z+x),求xyz/(xy+yz+xz)
1/x+1/y=1/2,1/y+1/z=1/3,1/x+1/z=1/6,求xyz/(xy+yz+xz)的值
X,Y,Z为实数,且XY/X+Y=1/3,YZ/Y+Z=1/4,XZ/X+Z=1/5,求XYZ/XY+YZ+XZ的值
已知x^3+y^3-z^3=96,xyz=4,x^2+y^2+z^2-xy+xz+yz=12,则x+y-z等于
x/(xy+x+1)+y/(yz+y+1)+z/(xz+z+1)=?其中 xyz=1
x-3=y-2=z-1,求x^2+y^2+z^2-xy-yz-xz的值