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

1 Answer
Aug 15, 2016

Answer:

#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)#