SOLUTION: What is the ratio of the nineteenth term to the twentieth term?????? 1,-3,9,-27,...

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Question 501518: What is the ratio of the nineteenth term to the twentieth term?????? 1,-3,9,-27,...
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
A general formula for this would be
+%28-1%29%5En+%2A+3%5En+ where n varies from
0 to any positive integer
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The ratio of the nineteenth term to the twentieth term:
+%28%28-1%29%5E18%2A3%5E18%29+%2F+%28%28-1%29%5E19%2A3%5E19%29+=+1+%2F+%28%28+-1%29%2A3%29+
++1+%2F+%28%28+-1%29%2A3%29+=+-%281%2F3%29+
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Note that I start counting terms with 0, so the
the 19th term has +n+=+18+
the 20th term has +n+=+19+