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

##### 1 Answer

Aug 15, 2016

#### 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)#