Find the 14th term of the geometric sequence 5,-10,20

Question

asked Sep 3, 2023 140k views

1 Answer

Xobotun · Answer 1 · 2023-09-08T10:24:16+0000

In this specific case, the initial term (a) is 5 and the common ratio (r) is -2

Henceforth, after determining what a and r are, we use the formula for the nth term. Which is:

a_n = a * r^(n-1)

Therefore, the 14th term is :

$\implies 5 * { (- 2)}^(14 - 1) \\\implies 5 * {( - 2)}^(13) \\ =\boxed { -40,960}$

Hope it helps!