Question

Q 10. If sum of n terms of an AP is Sn=n2 +2n +5, then
nth term of an AP is given by:
a. 2n + 1
b. 2n – 1
c. 2n + 3
d. n + 1​

Answer 1

Answer:

Step-by-step explanation:

Very simple

Tn=Sn -Sn-1= n^2 +2n +5 -((n-1)^2 +2(n-1)+5)=n^2 +2n -n^2 -1 +2n-2n+2 =2n+1

Option (a) is the correct answer