Question

A sequence is defined by the recursive formula f(n + 1) = 1.5f(n). Which sequence could be generated using the formula? –12, –18, –27, ... –20, 30, –45, ... –18, –16.5, –15, ... –16, –17.5, –19, ...

Answer 1

Answer: –12, –18, –27, ... [ A.K.A: (A.) ]

Answer 2

Formula f(n+1) = 1.5 f(n) => f(n+1) / f(n) = 1.5. That means, that you have to search for a sequence where the ratio of two consecutive terms is 1.5. The first sequence is the only one that meets that: - 18 / - 12 = 1.5 and - 27 / - 18 = 1.5. So, the answer is the first option: -12, -18, -27, ...