Question

How do you write an nth term rule for `r=8` and `a_1=-2`?

Answer 1

`a_n=(-2)(8)^(n-1)`

Explanation:

This is a `color(blue)"geometric sequence"`

with 1st term `a_1=-2" and common ratio " r=8`

The `color(blue)"nth term formula"` is found using.

`color(orange)"Reminder " color(red)(|bar(ul(color(white)(a/a)color(black)(a_n=ar^(n-1))color(white)(a/a)|)))`
where a is the first term and r, the common ratio.

here a = -2 and r = 8

`rArra_n=(-2)xx(8)^(n-1)`