Which recursive sequence would produce the sequence 1,0,−2,… ?a1=1 and an=3an−1−3a1=1 and an=−3an−1+3a1=1 and an=−2an−1+2a1=1 and an=2an−1−2
Q. Which recursive sequence would produce the sequence 1,0,−2,… ?a1=1 and an=3an−1−3a1=1 and an=−3an−1+3a1=1 and an=−2an−1+2a1=1 and an=2an−1−2
Given Sequence Determination: We are given the first term of the sequence, a1=1. We need to determine which recursive formula will generate the sequence 1,0,−2,… when applied starting from this first term.
Testing First Option: Let's test the first option: a1=1 and an=3an−1−3. We will calculate the second term using the first term.a2=3a1−3=3×1−3=0.This matches the second term of the given sequence.
Testing Second Option: Now, let's calculate the third term using the second term we just found. a3=3a2−3=3×0−3=−3.However, the third term of the given sequence is −2, not −3. Therefore, this recursive formula does not produce the given sequence.
Testing Third Option: Let's test the second option: a1=1 and an=−3an−1+3. We will calculate the second term using the first term.a2=−3a1+3=−3×1+3=0.This matches the second term of the given sequence.
Testing Fourth Option: Now, let's calculate the third term using the second term we just found. a3=−3a2+3=−3×0+3=3. However, the third term of the given sequence is −2, not 3. Therefore, this recursive formula also does not produce the given sequence.
Testing Fourth Option: Now, let's calculate the third term using the second term we just found. a3=−3a2+3=−3×0+3=3. However, the third term of the given sequence is −2, not 3. Therefore, this recursive formula also does not produce the given sequence.Let's test the third option: a1=1 and an=−2an−1+2. We will calculate the second term using the first term. a2=−2a1+2=−2×1+2=0. This matches the second term of the given sequence.
Testing Fourth Option: Now, let's calculate the third term using the second term we just found. a3=−3a2+3=−3×0+3=3.However, the third term of the given sequence is −2, not 3. Therefore, this recursive formula also does not produce the given sequence.Let's test the third option: a1=1 and an=−2an−1+2. We will calculate the second term using the first term.a2=−2a1+2=−2×1+2=0.This matches the second term of the given sequence.Now, let's calculate the third term using the second term we just found.a3=−2a2+2=−2×0+2=2.However, the third term of the given sequence is −2, not 2. Therefore, this recursive formula does not produce the given sequence.
Testing Fourth Option: Now, let's calculate the third term using the second term we just found.a3=−3a2+3=−3×0+3=3.However, the third term of the given sequence is −2, not 3. Therefore, this recursive formula also does not produce the given sequence.Let's test the third option: a1=1 and an=−2an−1+2. We will calculate the second term using the first term.a2=−2a1+2=−2×1+2=0.This matches the second term of the given sequence.Now, let's calculate the third term using the second term we just found.a3=−2a2+2=−2×0+2=2.However, the third term of the given sequence is −2, not 2. Therefore, this recursive formula does not produce the given sequence.Finally, let's test the fourth option: a1=1 and −20. We will calculate the second term using the first term.−21.This matches the second term of the given sequence.
Testing Fourth Option: Now, let's calculate the third term using the second term we just found. a3=−3a2+3=−3×0+3=3.However, the third term of the given sequence is −2, not 3. Therefore, this recursive formula also does not produce the given sequence.Let's test the third option: a1=1 and an=−2an−1+2. We will calculate the second term using the first term.a2=−2a1+2=−2×1+2=0.This matches the second term of the given sequence.Now, let's calculate the third term using the second term we just found.a3=−2a2+2=−2×0+2=2.However, the third term of the given sequence is −2, not 2. Therefore, this recursive formula does not produce the given sequence.Finally, let's test the fourth option: a1=1 and −20. We will calculate the second term using the first term.−21.This matches the second term of the given sequence.Now, let's calculate the third term using the second term we just found.−22.This matches the third term of the given sequence. Therefore, this recursive formula produces the given sequence.
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