Find the sum to n terms of an A. P whose k^th term is 5k+1

1.	Find the sum to n terms of an A. P whose k^th term is 5k+1
Answer» As, it is given that k th\xa0 term of the A.P. is 5k + 1.therefore, ak = a + (k – 1)d⇒ a + (k – 1)d = 5k + 1⇒ a + kd – d = 5k + 1now, on comparing the coefficient of k, we get,d\xa0= 5and\xa0\xa0a – d = 1⇒ a – 5 = 1⇒ a = 6

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