Q. If f(1)=10 and f(n)=−5f(n−1)−n then find the value of f(3).Answer:
Find f(2): Use the given recursive formula to find f(2). We know that f(1)=10. To find f(2), we use the formula f(n)=−5f(n−1)−n with n=2. f(2)=−5f(2−1)−2f(2)=−5f(1)−2f(2)=−5(10)−2f(2)=−50−2f(2)0
Calculate f(3): Use the value of f(2) to find f(3).Now that we have f(2)=−52, we can use the formula f(n)=−5f(n−1)−n with n=3.f(3)=−5f(3−1)−3f(3)=−5f(2)−3f(3)=−5(−52)−3f(3)=260−3f(2)0
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