Question

the sum of first nth term of an ap is given by sn=2n^2+n then the ap is​

Answer 1

Answer:

if sn=2n^2+n

then n=1

s1=2×1+1=3

n=2

s2=2×4+2=10

n=3

s3=2×9+3=21

so a1=s1=3

a2=s2-s1=10-3=7

a3=s3-s2=21-10=11

so we can see that the common difference between terms is 4

so the ap would be 3,7,11,15,19....