Question

The sum of the first n terms of an AP Sn1 is
$3 {n }^{2} + 6n$
Find the nth term of this AP.

Answer 1

Sn=3n2+6n

S(1)=3(1)2+6

=9

S(2)=12+12=24 a=9

D=15

Answer 2

This should be the answer. Hope it helps:)