Q. If a1=9 and an=−4an−1+4 then find the value of a3.Answer:
Find a2: We are given the first term of the sequence, a1=9, and the recursive formula for the sequence, an=−4an−1+4. To find a3, we first need to find a2 using the recursive formula.a2=−4a1+4Substitute the value of a1 into the formula.a2=−4(9)+4Calculate the value of a2.a2=−36+4a1=90
Calculate a3: Now that we have a2, we can use the recursive formula again to find a3.a3=−4a2+4Substitute the value of a2 into the formula.a3=−4(−32)+4Calculate the value of a3.a3=128+4a3=132
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