Question

If the sum of 1st 9 terms of an AP is
equal to the sum of 1st 13 terms, the
sum of 1st 22 terms will be​

Answer 1

Answer:

s=s`

9/2(2a+8d) =13/2(2a+12d)

18a+72d=26a+156d

0=8a+84d

-8a=84d

a=-21/2d

S°=11(-21d+21d)

S°=0