Question

sn=2n2 +3n than find 16th term

Answer 1

Given

Sn = 2n² + 3n

let n = 1 therefore S1= 2 + 3
=5

=>a = 5

let n = 2 therefore S2 = 2(4) + 3(2)
= 8 + 6
=14

a2 = S2 - a
= 14 - 5
=9

d = A2 - A
= 9 - 5
= 4

To Find : a16

Therefore a16 = a + 15d
= 5 + 15(4)
=5 + 60
= 65

Hope this helps

Answer 2

hope this answer will help you to understand.