Question 1026099: Write the sum using summation notation, assuming the suggested pattern continues.
8 - 40 + 200 - 1000 + ... Answer by ikleyn(52788) (Show Source):
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Write the sum using summation notation, assuming the suggested pattern continues.
8 - 40 + 200 - 1000 + ...
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8 - 40 + 200 - 1000 + ... = .
This is the sum of the first n terms of a geometric progression with the first term 8 and the common ratio (-5).
This sum is finite.
It can not be infinite since this series is divergent.
On geometricic progressions see the lesson Geometric progressions in this site, and the lessons associated with it.
