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Find the sum of first n terms of the ser...

Find the sum of first n terms of the series `3/1^2+5/(1^2+2^2)+7/(1^2+2^2+3^2) +....`.

A

`(6n)/(n+1)`

B

`(9n)/(n+1)`

C

`(12n)/(n+1)`

D

`(15n)/(n+1)`

Text Solution

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The correct Answer is:
A
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