Q. If f(1)=3,f(2)=1 and f(n)=f(n−1)−3f(n−2) then find the value of f(6).Answer:
Find f(3): Use the initial conditions to find f(3). The recursive formula is f(n)=f(n−1)−3f(n−2). We know f(1)=3 and f(2)=1. Calculate f(3) using the formula. f(3)=f(2)−3f(1)=1−3(3)=1−9=−8.
Find f(4): Use the recursive formula to find f(4). We now have f(2)=1 and f(3)=−8. Calculate f(4) using the formula. f(4)=f(3)−3f(2)=−8−3(1)=−8−3=−11.
Find f(5): Use the recursive formula to find f(5). We now have f(3)=−8 and f(4)=−11. Calculate f(5) using the formula. f(5)=f(4)−3f(3)=−11−3(−8)=−11+24=13.
Find f(6): Use the recursive formula to find f(6). We now have f(4)=−11 and f(5)=13. Calculate f(6) using the formula. f(6)=f(5)−3f(4)=13−3(−11)=13+33=46.
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