Q. If a1=7 and an+1=−3an+5 then find the value of a3.Answer:
Find a2: We are given the first term of the sequence, a1=7, and the recursive formula for the sequence, an+1=−3an+5. To find a3, we first need to find a2 using the recursive formula.Substitute n=1 into the recursive formula to find a2:a2=−3a1+5a2=−3(7)+5a2=−21+5a1=70
Find a3: Now that we have a2=−16, we can use the recursive formula again to find a3. Substitute n=2 into the recursive formula to find a3: a3=−3a2+5a3=−3(−16)+5a3=48+5a3=53
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