(x+y+z)(xy+yz+zx)等于多少
(x分之一加y分之一加z分之一)乘xy+yz+zx分之xy等于多少?急 急
(1/x+1/y+1/z)×(xy)/(xy+yz+zx)
xy+yz+zx=1,求x√yz+y√zx+z√xy
证明 (x+y+z)^2>3(xy+yz+zx)
分解因式:xyz-yz-zx-xy+x+y+z-1
xy+yz+zx=1,x,y,z>=0
已知xy:yz:zx=3:2:1,求①x:y:z ②x/yz:y/zx
化简x^2-yz/[x^2-(y+z)x+yz]+y^2-zx/[y^2-(z+x)y+zx]+z^2-xy/[z^2-
xy(x^2-y^2)+yz(y^2-z^2)+zx(z^2-x^2)
XYZ满足XY/X+Y=-2,YZ/Y+Z=3/4,ZX/Z+X=-4/3,求XYZ/XY+YZ+ZX的值
运用运算律计算:1/x+y+z*(1/x+1/y+1/z)×1/xy+yz+zx*1/xy+1/yz+1/zx
x+y分之xy=5,y+z分之yz=2分之7,z+x分之zx=4,则xy+yz+zx分之xyz=?