SOLUTION: The second term of a geometric sequence is 10 and the fifth term is 7290. find the nth term

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Question 442499: The second term of a geometric sequence is 10 and the fifth term is 7290. find the nth term
Answer by ewatrrr(24785) About Me  (Show Source):
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Hi

a%5Bn%5D+=+a%5B1%5D%2Ar%5E%28n-1%29

a%5B2%5D+=+a%5B1%5D%2Ar+=+10+  a%5B1%5D = 10/r

a%5B5%5D+=+a%5B1%5D%2Ar%5E4+=+7290

            10/r * r^4 = 7290

                  10r^3 = 7290

                      r^3 = 729

                       r = 9  and a%5B1%5D = 10/r = 10/9

a%5Bn%5D+=+%2810%2F9%29%2A9%5E%28n-1%29



CHECKING our Answer***

a%5B5%5D+=+%2810%2F9%29%2A9%5E%284%29+=+10%2F9%2A6561+=+7290









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