Question

poti sa ma ajuti 1+2+3......+100. Acum repede terog

Answer 1

$1 + 2 + 3 + ... + 100 = \frac{100(100 + 1)}{2}$

$= \frac{100 \times 101}{2} = 50 \times 101 = 5050$

$formula \: : \: 1 + 2 + 3 + ... + n = \frac{n(n + 1)}{2}$

Answer 2

1+2+3+....+100
(100.101):2
10100:2
5050