首先把你题目用式子表述是,
(y-z)^2+(x-y)^2+(z-x)^2=(y-z-2x)^2 ①
根据(1)的题意
(y-z)^2+(x-y)^2+(z-x)^2=(y-z-2x)^2 +(x+z-2y)^2+(x+y-2z)^2 ②
根据式子① ②得,(x+z-2y)^2+(x+y-2z)^2=0
则,x+z-2y=0 ③ 转化为 x-2y=-z ⑤
x+y-2z=0 ④ x+y=2z ⑥
解⑤ ⑥ 方程得x=y=z
则,原式=1