.If S, denotes the sum of n-terms of an APwhose common difference is d – InterviewSolution

1.

.If S, denotes the sum of n-terms of an APwhose common difference is d and firstterm is a, find Sn-2Sn-1ă Sn-2

Answer»

Given,aanddare the first term and common difference of the A.P.

Sum ofnterm of the A.P,Sn= n/2[2a+(n-1)d]

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