Question

If the sum of n terms of an A.P. be 3n² + n and its common difference is 6, then its first term is

 A. 2 

B. 3 

C. 1 

D. 4

Answer 1

Correct answer is (D). 4

Here, S_n= 3n² + n 

d = 6 

Putting n= 1 

S₁ = 3 + 1 = 4 

Sum of first 1 term = first term = 4