Q. If a1=1 and an=3an−1−n then find the value of a5.Answer:
Given Sequence and Formula: We are given the first term of the sequence, a1=1, and the recursive formula an=3an−1−n. To find a5, we need to find the values of a2, a3, a4, and then a5 using the recursive formula.
Find a2: First, let's find a2 using the recursive formula:a2=3a1−2a2=3(1)−2a2=3−2a2=1
Find a3: Next, we find a3 using the value of a2:a3=3a2−3a3=3(1)−3a3=3−3a3=0
Calculate a4: Now, we calculate a4 using the value of a3:a4=3a3−4a4=3(0)−4a4=0−4a4=−4
Find a5: Finally, we find a5 using the value of a4: a5=3a4−5 a5=3(−4)−5 a5=−12−5 a5=−17
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