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The sum of the first n terms of the seri...

The sum of the first n terms of the series `1^2+2.2^2+3^2+2.4^2+5^2+2.6^2+........ is (n(n+1)^2)/2` when n is even. When n is odd the sum is

A

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

B

`(n(n+1)(2n+1))/6`

C

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

D

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

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The correct Answer is:
A
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PATHFINDER-PROGRESSION AND SERIES -QUESTION BANK
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