Răspuns :
[tex]1 + 2 + 3 + ... + 100 = \frac{100(100 + 1)}{2} [/tex]
[tex] = \frac{100 \times 101}{2} = 50 \times 101 = 5050[/tex]
[tex]formula \: : \: 1 + 2 + 3 + ... + n = \frac{n(n + 1)}{2} [/tex]
[tex] = \frac{100 \times 101}{2} = 50 \times 101 = 5050[/tex]
[tex]formula \: : \: 1 + 2 + 3 + ... + n = \frac{n(n + 1)}{2} [/tex]