Question

Which recursive formula can be used to generate the sequence shown, where f(1) = 5 and n > 1?

5,–1, –7, –13, –19, ...

f(n + 1) = f(n) + 6
f(n) = f(n +1) – 6
f(n +1) = f(n) – 6
f(n +1) = –6f(n)

Answer 1

f(n + 1) = f(n) − 6

Reason: each term decreases by 6. With f(1)=5, f(2)=5−6=−1, f(3)=−1−6=−7, etc.