Question

Find the fourth term

Answer 1

f(1) = 5

f(n) = f(n - 1) + 8

Fine, we only know f(1), so, we we need to turn f(n - 1) into f(1), to do this let's call n = 2

f(2) = f(2 - 1) + 8

f(2) = f(1) + 8

f(2) = 5 + 8

f(2) = 13

We can do this for 3 too because f(n - 1) to 3 is f(2) and we discovered it.

f(3) = f(3 - 1) + 8

f(3) = f(2) + 8

f(3) = 13 + 8

f(3) = 21

And the same for 4.

f(4) = f(4 - 1) + 8

f(4) = f(3) + 8

f(4) = 21 + 8

f(4) = 29

So the fourth term is 29, rounding to the nearest tenth its 29