Mark the correct alternative in the following:
If the sum of n terms of an A.P. is 2, then its nth term is
Here, Sn=2n2+5n
∴ S1=2+5=7
∴ a1=S1=7
And S2=2×22+5×2=18
Now,a2=S2-S1=18-7=11
∴ d=a2-a1=11-7=4
Now, an=a1+(n-1)d
=7+(n-1)4
=7+4n-4
=4n+3