Q. If a1=8 and an=−4an−1−n then find the value of a4.Answer:
Given Information: We are given the first term of the sequence, a1=8, and the recursive formula for the sequence, an=−4an−1−n. To find a4, we need to find the values of a2 and a3 first.
Find a2: Let's find a2 using the recursive formula:a2=−4a1−2a2=−4(8)−2a2=−32−2a2=−34
Find a3: Now, let's find a3 using the recursive formula:a3=−4a2−3a3=−4(−34)−3a3=136−3a3=133
Find a4: Finally, we can find a4 using the recursive formula:a4=−4a3−4a4=−4(133)−4a4=−532−4a4=−536
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