Question

Algebra I function help?

Answer 1

So I have this question:

Bill is able to save $35/week after working part-time and paying his expenses. These two formulas show his weekly savings:
f(1) = 35, f(n) = f(1) + f(n-1) for n > 1
f(n) = 35n

A. Which one of these formulas show the sequence written recursively and which shows it written explicitly? Justify your explanations.
B. Use the recursive formula to make a table of values for 1 ≤ n ≤ 5. Show your calculations. Explain what your table means.
C. Use any formula of your choice to find f(40). Explain why you chose that method and what your answer means. Show your calculations.
D. Given the sequence of numbers: 5, 6, 8, 11, 15, 20, 26, 33, 41,… Explain whether or not this sequence can be considered a function.

Answer 2

I've solved all the way up to C. I understand how to use function formulas, but what formula are they suggesting I use? Do I make my own?

Answer 3

I thought maybe they meant pick from the explicit or recursive. I would rather use the recursive (not quite sure how to use explicit formula) but does that mean they really expect me to do f(1)-f(39) ?