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प्रश्न
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`
उत्तर
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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