1+2+3...+2017=?????????

Răspuns :

1 + 2 + 3 + ....  + 2017 = 

= 2017( 2017 + 1 ) : 2

= 2017 x 2018 : 2

= 2017 x 1009 

= 2035153
[tex]2017 (2017 + 1)supra 2 \: egal \: 2017 \times 2018supra \: 2 \: simplifici2cu \: 2018 \: prin \: 2 \: egal \: cu \: 2017 \times 1009 = 2035153[/tex]