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The sum of the series 2/3+8/9+(26)/(27)+...

The sum of the series `2/3+8/9+(26)/(27)+(80)/(81)+` to `n` terms is `n-1/2(3^(-n)-1)` (b) `n-1/2(1-3^(-n))` (c) `n+1/2(3^n-1)` (d) `n-1/2(3^n-1)`

A

`n - (1)/(2)(3^(n) -1)`

B

`n + (1)/(2) (3^(n) - 1)`

C

`n -(1)/(2)(1 - 3^(-n))`

D

`n + (1)/(2)(3^(-n) -1)`

Text Solution

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The correct Answer is:
B
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