已知x-y=(1+√3)/2,z-y=(1-√3)/2,求x²+y²+z²-xy-yz-xz的值.RT,我解不出来了.

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已知x-y=(1+√3)/2,z-y=(1-√3)/2,求x²+y²+z²-xy-yz-xz的值.RT,我解不出来了.
已知x-y=(1+√3)/2,z-y=(1-√3)/2,求x²+y²+z²-xy-yz-xz的值.
RT,我解不出来了.

已知x-y=(1+√3)/2,z-y=(1-√3)/2,求x²+y²+z²-xy-yz-xz的值.RT,我解不出来了.
x-y=(1+√3)/2 .(1)
z-y=(1-√3)/2 .(2)
(1)-(2):(x-z)=√3 .(3)
(1)²+(2)²+(3)²得:
(x-y)²+(z-y)²+(x-z)² = [(1+√3)/2]²+[(1-√3)/2)]²+[√3]²
2x²+2y²+2z²-2xy-2yz-2xz = 5
x²+y²+z²-xy-yz-xz = 5/2