find the sum of `n` terms of the series `(4-1/n)+(4-2/n)+(4-3/n)+..... – InterviewSolution

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1.	find the sum of `n` terms of the series `(4-1/n)+(4-2/n)+(4-3/n)+...........`
Answer» Correct Answer - `(1)/(2)(7n-1)` Required sum = (4+4+… to n terms) `-((1)/(n) + (2)/(n) + (3)/(n) +… + (n)/(n))` ` = 4n - (n)/(2)((1)/(n) + (n)/(n)) ["sum" = (n)/(2)(a+l)]` ` = 4n -((1+n))/(2) = (1)/(2) (7n-1).`

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