Question

What is the explicit formula for this geometric sequence?
8,4, 2, 1, ...

Answer 1

`a_(n)` = 8 *
`0.5^(n-1)`

Explanation:

First find the common ratio

r = 4/8 = 1/2

and first term is 8

a_n = a_1 * r^(n-1)

a_n = 8 * (1/2)^(n-1)

`a_(n)` = 8 *
`0.5^(n-1)`