Question

calcule a soma dos 15 primeiros termos da pg ( 5 10 20​

Answer 1

q = A2/A1

q = 10/5

q = 2

Sn = a1 . (q^n - 1) / q - 1

S15 = 5 . 2^15 - 1 / 2-1

S15 = 5. 32768 - 1 / 1

S15 = 163.840 - 1

S15 = 163839