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If a(1), a(2),a(3), cdots , a(2n+1) are ...

If `a_(1), a_(2),a_(3), cdots , a_(2n+1)` are in A.P then `(a_(2n+1)-a_(1))/(a_(2n+1)+a_(1)) + (a_(2n)-a_(2))/(a_(2n)+a_(2))+cdots+ (a_(n+_2)-a_(n))/(a_(n+2)+a_(n))` is equal to

A

A) `(n(n+1))/(2). (a_(2)-a_(1))/(a_(n+1))`

B

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

C

C) `(n+1)(a_(2)-a_(1))`

D

D ) None of these

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