Given m is a real number,and|1-m|=|m|+1,simplify an algebraic expression,then√m^2-2m+1=
问题描述：
Given m is a real number,and|1-m|=|m|+1,simplify an algebraic expression,then√m^2-2m+1=
A |m|-1 B -|m|-1 C m-1 D-m+1
答
D
|1-m|=|m|+1得m=