Question

Determine whether the following set of numbers is part of an arithmetic or geometric sequence. In the space provided, type arithmetic or geometric as your answer. -2, 4, -8, 16, ...

Answer 1

Explanation:

It's geometric.

You are starting with -2 and multiplying each successive term by - 2

r = - 2

a1 = -2

tn = ar^(n - 1)

So to try it out, let n be the 4th term

t4 = -2 * (-2)^(4 - 1)

t4 = - 2 * (-2)^3

t4 = - 2 * -8

t4 = 16 just as the series indicated.