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Let a1, a2, a3, ...an be an AP. Prove th...

Let `a_1, a_2, a_3, ...a_n` be an AP. Prove that: `1 / (a_1 a_n) + 1 / (a_2 a_(n-1)) + 1 /(a_3a_(n-2))+......+ 1 /(a_n a_1) = `

A

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

B

`(n)/(a_(1) + a_(n))`

C

`(1)/(a_(1) + a_(n))`

D

`(n -1)/(a_(1) + a_(n))`

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The correct Answer is:
A
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DISHA PUBLICATION-SEQUENCES AND SERIES -Exercise -2 : Concept Applicator
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