Question 1100185
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what is the sum of a+ar+ar^2.....to infinity when r<1.
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It is the sum of an infinite geometric progression.


Infinite geometric progression with the common ratio "r" converges  <U>IF AND ONLY IF</U>   |r| < 1.


Then its sum is  S = {{{a/(1-r)}}},  where  "a" is the first term.
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