Question

which sequence is generated by the function $f(n + 1) = f(n) - 2$ for $f(1) = 10$?
-10, -12, -14, -16, -18, ...
-2, 8, 18, 28, 38, ...
8, 18, 28, 38, 48, ...
10, 8, 6, 4, 2, ...

Explanation:

Step1: Identify initial term

$f(1) = 10$

Step2: Calculate 2nd term

$f(2) = f(1) - 2 = 10 - 2 = 8$

Step3: Calculate 3rd term

$f(3) = f(2) - 2 = 8 - 2 = 6$

Step4: Calculate 4th term

$f(4) = f(3) - 2 = 6 - 2 = 4$

Step5: Calculate 5th term

$f(5) = f(4) - 2 = 4 - 2 = 2$

Answer:

10, 8, 6, 4, 2, ...