Q. If f(1)=1 and f(n)=−5f(n−1)−n then find the value of f(3).Answer:
Given f(1)=1: We are given f(1)=1. To find f(3), we first need to find f(2) using the recursive formula f(n)=−5f(n−1)−n. Substitute n=2 into the formula to find f(2). f(2)=−5f(2−1)−2f(2)=−5f(1)−2f(2)=−5(1)−2f(1)=10f(1)=11
Find f(2): Now that we have f(2)=−7, we can use it to find f(3) using the same recursive formula.Substitute n=3 into the formula to find f(3).f(3)=−5f(3−1)−3f(3)=−5f(2)−3f(3)=−5(−7)−3f(3)=35−3f(3)=32