In A.P the sum of first "n" terms is 3n^2/2+13n/2. Find the 25 term of

1.	In A.P the sum of first "n" terms is 3n^2/2+13n/2. Find the 25 term of A.P
Answer» Sum of n terms = 3n2/2 +13n/2Put n = 1, we get sum of 1 term = first term = 3/2+13/2= 16/2= 8So first term =8\xa0put n = 2, we get S2 =\xa03(2)2/2 +132/2 = 34/2 +132/2 = 6+13= 19So second term = 19-8 = 11So A.P is 8 ,11,14,17.........\xa0a= 8 and d=3a25 =\xa0a+(25-1)d = 8+243= 8+72 = 80\xa0 Put the value of n Ans will be 80

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