3k square _k ,d=6 find first term

1.	3k square _k ,d=6 find first term
Answer» Let the sum of k terms of A.P. is Sn = 3k2\xa0- kNow kth term of A.P = Sn - Sn-1ak = (3k2 - k) - [3 (k - 1)2- ( k - 1)]= (3k2 - k) - [3 (k2- 2k + 1)- ( k - 1)]= 3k2 - k - [ 3k2\xa0-6k + 3 - k + 1]= 3k2 - k - [ 3k2\xa0-7k + 4 ]= 3k2\xa0- k - 3k2 + 7k- 4= 6k - 4first term = a =\xa0{tex}6 \\times 1 - 4 = 6 - 4 = 2{/tex}

Discussion