Question

= 2018¹ +2 (1+2+3+...+2017)
Dau coroana,va rog mult

Answer 1

Răspuns:

Explicație pas cu pas:

2018¹+2(1+2+3+...+2017)=2018+2·2017·2018/2=2018(1+2017/2)=

2018(2+2017)/2=1009·2019=2037171

Am folosit formula sumei lui Gauss: 1+2+3+...+n=n·(n+1)/2