Question

Calcule a soma 100 primeiros termos da pg (1,4,16)

Answer 1

P.G.(1, 4, 16, ...)

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

S100 = a1.q^100-1/q-1

q = a2/a1

q = 4/1

q = 4

S100 = 1.4^100 - 1/4 - 1

S100 = (4^100 - 1)/3