计算11×13\2+13×15\2+15×17\2+17×19\2+19×21\2+21×23\2

问题描述:

计算11×13\2+13×15\2+15×17\2+17×19\2+19×21\2+21×23\2

11×13\2+13×15\2+15×17\2+17×19\2+19×21\2+21×23\2
=1/11-1/13+1/13-1/15+1/15-1/17+1/19-1/21+1/21-1/23
=1/11-1/23
=12/253