Q. If f(1)=5,f(2)=4 and f(n)=3f(n−1)−f(n−2) then find the value of f(5).Answer:
Find f(3): Use the given recursive function and initial conditions to find f(3). The recursive function is f(n)=3f(n−1)−f(n−2). We know f(1)=5 and f(2)=4. Calculate f(3) using the recursive function. f(3)=3f(2)−f(1)=3(4)−5=12−5=7.
Find f(4): Use the recursive function to find f(4). We now know f(2)=4 and f(3)=7. Calculate f(4) using the recursive function. f(4)=3f(3)−f(2)=3(7)−4=21−4=17.
Find f(5): Use the recursive function to find f(5). We now know f(3)=7 and f(4)=17. Calculate f(5) using the recursive function. f(5)=3f(4)−f(3)=3(17)−7=51−7=44.
More problems from Write and solve direct variation equations