Tổng 1 + C1 2017 + C2 2017 +...+ C2017 2017 bằng11/50Tổng 1+C20171+C20172+...+C20172017 bằng22017.22017+1. 22017-1. 22018.Giải thíchChon A Ta có 1+12017=C20170+C20171+C20172+...+C20172017⇔1+C20171+C20172+...+C20172017=22017.