（三次根号X-1）+1=X
（三次根号X-1）=x-1 三次方得
x-1=(x-1)^3
(x-1)^3-(x-1)=0
(x-1)((x-1)^2-1)=0
(x-1)(x-1+1)(x-1-1)=0
x(x-1)(x-2)=0
x=0 或 x＝1 或x＝2