The function f(n) = 3f(n-2) - f(n-1), where f(2) = 3 and f(1) = -1. What is the value of f(5)?
3f ( n - 2) - f(n - 1)
So
f(1) =
3f (-1) - f(0) = -1
f(2) =
3 f(0) - f (1) = 3
f(3) =
3f(1) - f (2) = 3 (-1) - 3 = -6
f (4) =
3 f(2) - f(3) = 3(3) - (-6) = 15
f(5) =
3f(3) - f (4) = 3(-6) - 15 = - 33
