Question

The sum of n terms of an ap is sn= 1/2(n²+n) then it's common difference is?​

Answer 1

Step-by-step explanation:

s1= a1= (1/2)(1+1)=1

s2=(1/2)(4+2)=3

a2= s2-s1=3-1=2

so common difference =a2-a1= 1