3a-b/m-n-( )=3a-b/m
问题描述:
3a-b/m-n-( )=3a-b/m
答
3a-b/m-n-( )=3a-b/m
3a-b/m-n-(3a-b/m)=()
()=3a-b/m-n-3a+b/m=-n