Question

find the sum of first 24terms of the list of numbers whose nth term is given by an =3+2
$find the sumoffirst24termsof listofnumberswhosenthtermisgivenbyan = 3 + 2n$

Answer 1

an=3+2n
then a1=5
a2=3+4=7
a3=3+6=9
then
a=5 & d=2
then
S24=(24/2)(2×5+23×2)
=12×(10+46)
=12×56
=672