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If Sn=n P+(n(n-1))/2Q ,w h e r eSn denot...

If `S_n=n P+(n(n-1))/2Q ,w h e r eS_n` denotes the sum of the first `n` terms of an A.P., then find the common difference.

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CENGAGE PUBLICATION-SEQUENCES AND SERIES-All Questions
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