How do i solve this being a geometric funtion?

Question

t(2)=1 and t(5)=1/8 please give me in details

Answer 1

Let a be the first term of the geometric series, and r the common ratio,

The first 5 terms are:

a, ar, ar^2, ar^3, ar^4, ar^5.

t(5) = 1 / 8

ar^4 = 1 / 8 ...(1)

t(2) = 1

ar = 1 ...(2)

Dividing (1) by (2):

r^3 = 1 / 8

r = 1 / 2.

Substituting for r in (2):

a = 2.

The first 5 terms are:

2, 1, 1 / 2, 1 / 4, 1 / 8.