已知x,y,z,为实数,x^2+y^2=1,y^2+z^2=2,x^2+z^2=2,求xy+yz+xz=

已知x,y,z均为实数,且满足:x+2y-z=6,x-y+2z=3.求x+y+z的最小值 已知x,y,z为正实数,满足x-y+2z=0,求y²/(xz)的最小值 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 已知正实数x,y,z 满足2x（x+1/y+1/z)=yz,,则(x+1/y)(x+1/z) 的最小值为 . 已知X Y Z为正实数,且不全相等,求证X^2/Y+Y^2/Z+Z^2/X>X+Y+Z 已知实数x,y,z,满足那么x+y=6,z^2=xy-9,求(x+y)^z 已知x,y,z为实数,且x+y+z=1,x^2+y^2+z^2=3,则xyz的最大值是 已知x,y,z为实数,且x+y+z=8,x^2+y^2+z^2=24,求证：4/3 已知实数x、y、z满足：2x+3y+z=1,则x²+y²+z²的最小值为 x+y+z+2=xyz,x,y,z.为正实数,证明：xyz(x-1)(y-1)(z-1) 已知实数x,y,z满足x+y+z=2根号x-1+2根号y-1+2根号z-1求X+2Y+3Z 已知实数x,y,z满足关系式2x-3y-z=0,x-2y+z=0,求x比y比z的值 已知实数xyz满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3求x+y+z的值 已知实数 x y z 满足x+y-z=0 ,3x-y+2z=0 则x :y :z 已知三个实数x,y,z满足条件(z-x)^2-4(x-y)(y-z)=0,求证:x,y,z成等差数列 已知实数x,y,z满足x=6-y,z^2=xy-9,求证：x=y 已知三个正实数x y z,且x+y+z=1,证明(x^2+y^2+z^2)(z/(x+y)+x/(y+z)+y/(z+x))>=1/2