17. In an A.P. the sum of first n terms is 3n^2\5+13n/2. Find the 25th

1.	17. In an A.P. the sum of first n terms is 3n^2\5+13n/2. Find the 25th term
Answer» n term sum = 3n²/2 + 13n/2as we know that nth term = (Sum of nth term ) -( sum of (n-1)th term)method 1so 25th term = (sum of 25 terms) - ( sum of 24 terms) =(3×(25)²/2 +(13×25)/2) - ( 3×(24)²/2 + (13×24)/2) = 1100 - 1020 = 80method 21st term = 8sum of 2 terms = 192nd term = 19 - 8= 11so. DIFFERENCE = 11- 8 = 325th term = (8 + (25 -1)×3) = 80

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