SOLUTION: Does the following infinite geometric series diverage or converge? explain. 7+21+63+189...

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Question 448471: Does the following infinite geometric series diverage or converge? explain. 7+21+63+189...
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,



7+21+63+189...  = sum%28+7%283%29%5E%28n-1%29%2C+n=1%2C+6+%29 

or 

   where r = 3

  sum%28+7%2A%283%29%5E%28n-1%29%2C+n=1%2C+infinity+%29+=+7%28%281-3%5En%29%2F%28-2%29%29

     r = 3 >1  Series diverges