Q. If f(1)=0,f(2)=5 and f(n)=2f(n−1)−2f(n−2) then find the value of f(5).Answer:
Find f(3): Use the initial conditions to find f(3). The recursive formula is f(n)=2f(n−1)−2f(n−2). We know f(1)=0 and f(2)=5. Now calculate f(3) using the formula. f(3)=2f(2)−2f(1)=2×5−2×0=10−0=10.
Find f(4): Use the recursive formula to find f(4). We have f(2)=5 and f(3)=10. Now calculate f(4) using the formula. f(4)=2f(3)−2f(2)=2×10−2×5=20−10=10.
Find f(5): Use the recursive formula to find f(5). We have f(3)=10 and f(4)=10. Now calculate f(5) using the formula. f(5)=2f(4)−2f(3)=2×10−2×10=20−20=0.
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