SOLUTION: The sum of the first n terms of a series is 2n^2−n. Find the nth term

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Question 1047951: The sum of the first n terms of a series is 2n^2−n. Find the nth term
Answer by ikleyn(52776) About Me  (Show Source):
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The sum of the first n terms of a series is 2n^2−n. Find the nth term
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a%5Bn%5D = S%5Bn%5D - s%5Bn-1%5D = 2%2An%5E2+-n - %282%2A%28n-1%29%5E2+-+%28n-1%29%29 = 2n%5E2+-+n+-+2n%5E2+%2B+4n+-+2+%2B+n+-+1 = 4n-3.


Answer.  a%5Bn%5D = 4n-3.