SOLUTION: Find S15 for the series -1 + -3 + -5 + -7 +...

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Question 1126514: Find S15 for the series -1 + -3 + -5 + -7 +...
Answer by ikleyn(52794)   (Show Source): You can put this solution on YOUR website!
.
= - (1 + 3 + 5 + 7 + . . . ) =  = .


HINT.  The sum of the first n odd positive integer numbers is equal to .

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