Question

A sequence is defined by the formula f(n + 1) = f(n) – 3. If f(4) = 22, what is f(1)?

Answer 1

f(3 +1) = f(3) - 3
f(4) - f(3) = -3

22 - f(3) = -3
f(3) = 22+3 = 25

so f(2) = 25 + 3 = 28

and f(1) = ?

Answer 2

28?

Answer 3

No f(2) = 28

Answer 4

do you see the pattern
the terms are going down 3 as we start form 1
? 28,25,22 etc

so what would be the first term?