Question

4- Calcule a soma dos termos da P.G. (20, 10, 4, ... ).​

Answer 1

a1 = 20

q = 10/20 = 1/2

S(n) = a1/(1 - q)

S(n) = 2/(1 - 1/2)

S(n) = 2/(0,5)

S(n) = 4

Resposta: 4