Which recursive sequence would produce the sequence 8,−28,80,… ?a1=8 and an=−4an−1−3a1=8 and an=−3an−1−4a1=8 and an=4an−1−4a1=8 and an=−4an−1+4
Q. Which recursive sequence would produce the sequence 8,−28,80,… ?a1=8 and an=−4an−1−3a1=8 and an=−3an−1−4a1=8 and an=4an−1−4a1=8 and an=−4an−1+4
Identify First Term: Identify the first term of the sequence.The first term given is a1=8.
Calculate Second Term: Use the first recursive formula to calculate the second term.The first option is an=−4an−1−3. Let's calculate a2:a2=−4a1−3=−4(8)−3=−32−3=−35.This does not match the second term of the sequence, which is −28.
Calculate Third Term: Use the second recursive formula to calculate the second term.The second option is an=−3an−1−4. Let's calculate a2:a2=−3a1−4=−3(8)−4=−24−4=−28.This matches the second term of the sequence.
Verify Pattern - Third Formula: Use the second recursive formula to calculate the third term.Let's calculate a3 using the second option:a3=−3a2−4=−3(−28)−4=84−4=80.This matches the third term of the sequence.
Verify Pattern - Fourth Formula: Verify the pattern with the third recursive formula.The third option is an=4an−1−4. Let's calculate a2:a2=4a1−4=4(8)−4=32−4=28.This does not match the second term of the sequence, which is −28.
Calculate Third Term: Verify the pattern with the fourth recursive formula.The fourth option is an=−4an−1+4. Let's calculate a2:a2=−4a1+4=−4(8)+4=−32+4=−28.This matches the second term of the sequence, but we need to check the third term to be sure.
Calculate Third Term: Verify the pattern with the fourth recursive formula.The fourth option is an=−4an−1+4. Let's calculate a2:a2=−4a1+4=−4(8)+4=−32+4=−28.This matches the second term of the sequence, but we need to check the third term to be sure.Use the fourth recursive formula to calculate the third term.Let's calculate a3 using the fourth option:a3=−4a2+4=−4(−28)+4=112+4=116.This does not match the third term of the sequence, which is 80.
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