The sum of first n terms of an AP is `(5n - n^(2)).` The nth term of t – InterviewSolution

InterviewSolution

1.	The sum of first n terms of an AP is `(5n - n^(2)).` The nth term of the AP isA. (5-2n)B. (6-2n)C. (2n -5)D. (2n-6)
Answer» Correct Answer - B `T_(n) = (S_(n) - S_(n - 1)) = (5n-n^(2)) - {5(n-1) - (n-1)^(2)} = (5n -n^(2)) - (7n-n^(2)-6) = (6 -2n)`

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