已知分式m-3/m-2与分式2m/2-m互为相反数,则m=?

题目

已知分式m-3/m-2与分式2m/2-m互为相反数,则m=?

答案

分式(m-3)/(m-2)与分式2m/(2-m)互为相反数
即(m-3)/(m-2)+2m/(2-m)=0
(m-3)/(m-2)-2m/(m-2)=0
(m-3-2m)/(m-2)=0
(m-3)/(m-2)=0
m=3
经检验m=3是方程的解