Question

if sum of first n term of an AP is given Sn=2n^2+3n. find the sixteenth term of an ap

Answer 1

of the AP -

ist term = 2(1)^2 + 3(1) = 2 + 3 = 5
2nd term = 2(2)^2 + 3(2) = 8+6=14

common difference = 14 - 5 = 9

16th term = a+(n-1)d
= 5 + (16-1)(9)
= 5 + 135
=140