Question

determine o número de termos da pg 128,64,32... 1/256

Answer 1

a1 = 128
an = 1/256
q = 1/2
an = a1.q^(n-1)
q^(n-1) = an/a1 =1/256.1/128 = 1/32768 = 1/2^15
1/2^(n-1) = 1/2^15
(n-1) = 15
n = 16