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) - 3
The first term of a sequence: A 1 = 2 + 9 ( 1 - 1 ) = 2 The 2nd term of a sequence: A 2 = 2 + 9 ( 2 - 1 ) = 2 + 9 = 11 The common difference is: d = A2 - A1 = 11-2 = 9 The recursive formula is: B ) A (n) = A(n-1) +9