Question

Rezolva ecuatia:
1+2+3+...+1199+1200

Answer 1

$1+2+3+...+1199+1200 = \\ \\ = \frac{1200*1201}{2} = \\ \\ = 600*1201 = \\ \\ = 720600$

Sper ca te-am ajutat.

Answer 2

Formula lui Gaus:
1+2+3+4+...+n=n(n+1)/2;
1+2+3+...+1199+1200=1200·1201/2=
600·1201=720.600