If the sum of n terms of an A.P. be 3n 2 + n and its common difference is 6, then its first term is

Question

Philoid · Accepted Answer

Here, S_n= 3n² + n

d = 6

Putting n= 1

S₁ = 3 + 1 = 4

Sum of first 1 term = first term = 4