xy:yz:zx=2:3:5 求x:y:z
已知xy:yz:zx=3:2:1,求①x:y:z ②x/yz:y/zx
XYZ满足XY/X+Y=-2,YZ/Y+Z=3/4,ZX/Z+X=-4/3,求XYZ/XY+YZ+ZX的值
xy+yz+zx=1,求x√yz+y√zx+z√xy
已知三个数x,y,z,满足xy/x+y=-2,yz/y+z=4/3,zx/z+x=-4/3,求(xyz)/(xy+yz+
已知xy:yz:zx=3:2:1,求(x+y):z的值
时数x,y,z满足x+y+z=5,xy+yz+zx=3,求Z最大值
已知xy/x+y=3,yz/y+z=2,zx/z+x=1,求y的值
X+Y/XY=1,Y+Z/YZ=2,Z+X/ZX=3 求X的值
若x/3=y/2=z/5,且xy+yz+zx=93,求9x*x+12y*y+2z*z的值.
已知x+y+z=5,xy+yz+zx=9,求x^2+y^2+z^2的值
证明 (x+y+z)^2>3(xy+yz+zx)
已知x+y+z=2,xy+yz+zx=-5,求x²+y²+z²的值