Answer:
f(7) = 13.7
f(8) = 18.7
Recursive Function Is: f(1) = -16.3; (fn) = f(n - 1) + 5
Explanation:
The recursive function of the arithmetic sequence is
f(1) = first term; f(n) = f(n-1) + d, where
- d is the common difference between each two consecutive terms
∵ f(5) = 3.7 and f(6) = 8.7
∵ d = f(6) - f(5)
∴ d = 8.7 - 3.7
∴ d = 5
∵ f(7) = f(6) + 5
∴ f(7) = 8.7 + 5
∴ f(7) = 13.7
∵ f(8) = f(7) + 5
∴ f(8) = 13.7 + 5
∴ f(8) = 18.7
→ To find f(1) subtract from each term the value of d
∵ f(5) = f(4) + d
∴ f(4) = f(5) - d
∴ f(4) = 3.7 - 5
∴ f(4) = -1.3
∵ f(3) = f(4) - 5
∴ f(3) = -1.3 - 5
∴ f(3) = -6.3
∵ f(2) = f(3) - 5
∴ f(2) = -6.3 - 5
∴ f(2) = -11.3
∵ f(1) = f(2) - 5
∴ f(1) = -11.3 - 5
∴ f(1) = -16.3
∴ Recursive Function Is: f(1) = -16.3; (fn) = f(n - 1) + 5