已知x+y+z=2,xy+yz+zx=-5,求x²+y²+z²的值
已知x+y+z=2,xy+yz+zx=-5,求x²+y²+z²的值
已知2x-y-5z=0,x-2y+2z=0,求x²+y²+z²/xy+yz+zx的值.
1.已知4(xy-zx-y²+yz)=-z²+2zx-x²,求z-zy+x-3的值
已知x+y+z=5,xy+yz+zx=9,求x^2+y^2+z^2的值
已知x+y+z=1,x²+y²+z²=2求xy+yz+zx
已知x-y=y-z=3/5,x²+y²+z²=1.求xy+yz+zx的值
已知xy/x+y=3,yz/y+z=2,zx/z+x=1,求y的值
已知x-3=y-2=z-1,试求x²+y²+z²-xy-yz-zx的值
已知xy:yz:zx=3:2:1,求(x+y):z的值
若x/3=y/2=z/5,且xy+yz+zx=93,求9x²+12y²+2z²的值.
已知x-y=4,y-z=2,求x^2y+y^2z+z^2x-(xy^2+yz^2+zx^2)的值
已知x-y=4,y-z=2,求x^2y+y^2z+z^2x-(xy^2+yz^2+zx^2)的值.