Question

An arithmetic sequence is represented by the explicit formula A(n) = 2 + 9(n - 1). What is the recursive formula?

A. A(n) = A(n - 1) + 2

B. A(n) = A(n - 1) + 9

C. A(n) = A(n - 1) - 9

D. A(n) = A(n - 1) - 2

Answer 1

A(n-1) = 2+ (n-2)*9 = [2+ (n-1)*9] - 9 = ??

Answer 2

I don't know.

Answer 3

A(n-1) = 2+ (n-2)*9 = [2+ (n-1)*9] - 9 = A(n)-9
so
A(n) = A(n-1) + 9.

Answer 4

Ah, I see.

Answer 5

did u understand the adjustments i did?

Answer 6

Yes, thank you.

Answer 7

welcome :)