#1: Determine the general term, tn, for sequence/series 64, -16, 4, -1,... I have no idea how to do this
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Originally Posted by needhelpplease1 #1: Determine the general term, tn, for sequence/series 64, -16, 4, -1,... I have no idea how to do this Here's a clue: notice how each term is -1/4 times the previous term. This, and your notes, should help you find the answer.
Originally Posted by needhelpplease1 #1: Determine the general term, tn, for sequence/series 64, -16, 4, -1,... I have no idea how to do this $\displaystyle a_{n+1} = \frac{-a_n}{4}$ Note: This is the recurrence relation. The series is expressed as what mathemagister has stated: $\displaystyle {a_n} = [-(-1)^n] 4^{4-n} $
Last edited by harish21; Apr 8th 2010 at 11:20 AM.
And that translates to $\displaystyle a_n = -(-1)^n 4^{4-n}$
Originally Posted by mathemagister And that translates to $\displaystyle a_n = -(-1)^n 4^{4-n}$ wait, wouldn't it be $\displaystyle tn = 64(-1/4)^n$?
Originally Posted by needhelpplease1 wait, wouldn't it be $\displaystyle tn = 64(-1/4)^n$? No, because then when n = 1, you wouldn't get 64. EDIT: I think you were thinking of $\displaystyle t_n = 64(-1/4)^{n-1}$ which is also a correct way to express the sequence. Hope everything is clarified Mathemagister
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