Q. If f(1)=1,f(2)=0 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)=1 and f(2)=0. So, f(3)=f(2)−3f(1)=0−3(1)=−3.
Find f(4): Use the recursive formula to find f(4).Now we have f(2)=0 and f(3)=−3.So, f(4)=f(3)−3f(2)=−3−3(0)=−3.
Find f(5): Use the recursive formula to find f(5). We have f(3)=−3 and f(4)=−3. So, f(5)=f(4)−3f(3)=−3−3(−3)=−3+9=6.
Find f(6): Use the recursive formula to find f(6). We have f(4)=−3 and f(5)=6. So, f(6)=f(5)−3f(4)=6−3(−3)=6+9=15.
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