(m+3m+5m+...+2014m)-(2m+4m+6m+...+2013m)

问题描述:

(m+3m+5m+...+2014m)-(2m+4m+6m+...+2013m)

原式
=m+3m+5m+.2014m-2m-4m-6m-.2013m
=m-2m+3m-4m+5m-6m
=m+(3m-2m)+(5m-4m)+(2014m-2013m)
=m+m+.1007个m
=1007m