calculați prin suma lui Gauss
1. 1+2+3+...+30=
2. 1+2+3+...+60=
3. 1+2+3+...+200=

Răspuns:
1) = (30x31):2=930:2=465
2). = (60x61):2=2660:2=1830
3). =(200x201):2=40200:2=20.100
Răspuns:
1. 30×(30+1):2=
30×31:2=
15×31=
465
2. 60×(60+1):2=
60×61:2=
30×61=1830
3. 200×(200+1):2=
200×201:2=
100×201=
20100