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In an A.P., if pth term is 1/q and qth term is 1/p, prove that the sum of first pq terms is 1/2 (pq + 1) where p≠q

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Question

In an A.P., if pth term is 1/q and qth term is 1/p,  prove that the sum of first pq terms is 1/2 (pq + 1) where `p != q`

Sum
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Solution

It is known that the general term of an A.P. is an = a + (n – 1)d

∴ According to the given information,

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