SOLUTION: find a n for the following geometric sequence a1=4,r=-3

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Question 464968: find a n for the following geometric sequence a1=4,r=-3
Found 2 solutions by stanbon, Gogonati:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find a(n) for the following geometric sequence a1=4,r=-3
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a(n) = a(1)*r^(n-1)
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a(n) = 4*(-3)^(n-1)
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Cheers,
Stan H.

Answer by Gogonati(855) About Me  (Show Source):
You can put this solution on YOUR website!
First we find the first term of the sequence: a1=ao*r <=>ao=a1/r=-(4/3).
We know that a%5Bn%5D=a%5B0%5D%2Ar%5En, substituting we get: a%5Bn%5D=-%284%2F3%29%2A%28-3%29%5En
a%5Bn%5D=4%2A3%5E%28n-1%29.