Practicing Success
If f is a function such that f(0) = 2, f(1) = 3 and f(x+2) = 2f(x) – f(x+1) for every real x then f(5) is |
7 13 1 5 |
13 |
For x = 0, f(2) = 2f(0) – f(1) = 2 × 2 – 3 = 1, for x = 1, f(3) = 2f(1) – f(2) = 6 – 1 = 5, for x = 2, f(4) = 2f(2) – f(3) = 2 × 1 – 5 = -3, for x = 3, f(5) = 2f(3) – f(4) = 2 × 5 – (-3)= 13. Hence (B) is the correct answer. |