Question

In an A.P. if Sn = 3n2 - n and its common difference is ‘6’ then first term is ______

Answer 1

Answer:

In an A.P. if $S_n = 3n^2-n$ and its common difference is ‘6’ then first term is 2

Step-by-step explanation:

$S_n\text{ is the sum of first n terms of an A.P}$

$\text{Given:}$

$\bf\,S_n=3n^2-n$

$\text{put n=1, we get}$

$S_1=3(1)^2-(1)$

$S_1=3-1$

$S_1=2$

$\text{Sum of 1 term of the A.P=2}$

$\implies\text{First term}=2$