How do you find the sum of the infinite geometric series 12 + 6 + 3 + . . . ?
1 Answer
24
Explanation:
Let the series be
Consider the generic case: of
Let k be any constant
Let r be the geometric ratio
Then
Note that you could have
Multiply (1) by r giving:
(2) - (1) ginves:
Notice that the number sequence is reducing implying the
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To find r consider
Inverting
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To find k
so
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this matches so it is safe to assume we have found the system.
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Plug values for k and r in equation (3) and determine limits
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