Question

What is the `n^"th"` term of the geometric sequence `360,180,90,45`?

Answer 1

`T_n = 360*(1/2)^(n-1)`

Explanation:

A GP has the general term `T_n = ar^(n-1)`

In this case we have:

`T_1 =a = 360`

`r = T_n /T_(n-1) = 45/90=90/180 = 180/360 = 1/2`

Substituting these values gives: `T_n = 360*(1/2)^(n-1)`

This means that if we want to know the value of a particular term, we just need to plug in the value of `n`.