Which recursive sequence would produce the sequence 2,9,44,… ?a1=2 and an=6an−1−3a1=2 and an=5an−1−1a1=2 and an=−3an−1+6a1=2 and an=−an−1+5
Q. Which recursive sequence would produce the sequence 2,9,44,… ?a1=2 and an=6an−1−3a1=2 and an=5an−1−1a1=2 and an=−3an−1+6a1=2 and an=−an−1+5
Test First Option: We will test each recursive sequence option by applying the given formula to the initial term a1=2 and checking if it produces the sequence 2,9,44,…. We start with the first option:a1=2 and an=6an−1−3
Calculate Second Term: Calculate the second term using the first option's formula:a2=6a1−3a2=6×2−3a2=12−3a2=9This matches the second term of the sequence.
Calculate Third Term: Calculate the third term using the first option's formula:a3=6a2−3a3=6×9−3a3=54−3a3=51This does not match the third term of the sequence (which is 44), so the first option is incorrect.
Test Second Option: Now we test the second option: a1=2 and an=5an−1−1
Calculate Second Term: Calculate the second term using the second option's formula:a2=5a1−1a2=5×2−1a2=10−1a2=9This matches the second term of the sequence.
Calculate Third Term: Calculate the third term using the second option's formula:a3=5a2−1a3=5×9−1a3=45−1a3=44This matches the third term of the sequence, so the second option is correct.
Correct Recursive Sequence: We do not need to test the remaining options because we have found the correct recursive sequence that produces the sequence 2,9,44,….
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