If the sum of nterms of an A.P. in `n P" "+1/2n(n-1)Q ,`where P and Q – InterviewSolution

InterviewSolution

1.	If the sum of nterms of an A.P. in `n P" "+1/2n(n-1)Q ,`where P and Q are constants, find the commondifference.
Answer» Correct Answer - Q `S_(n)=nP+1/2n(n-1) Qrightarrow S_(n-1) = (n-1) P+1/2(n-1) (n-2) Q` ` T_(n) = ( S_(n)-S_(n-1)) = P ( n-1) Q Rightarrow T_(n-1) =P +(n-2)Q` ` d= (T_(n) -T_(n-1)=Q`

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