e sum of n terms of an A.P. is 3n2 +5n and its mth termof m.is 164, fi – InterviewSolution

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1.	e sum of n terms of an A.P. is 3n2 +5n and its mth termof m.is 164, find the valueInsert five numbers between 8 and 26 such that the resulting sequence is an AP
Answer» S = 3n^2+ 5nS1= a1= 3+5 = 8S2= a1+ a2 = 22 ⇒a2= 22 - 8 = 14d = 14 - 8 = 6am = a + (m - 1)d164 = 8 + (m - 1)6(m - 1)6 = 156 m - 1 = 26 m = 27

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