Question

the sum of the first n terms of an AP is given by Sn=(2nsquare +5n) find nth term of AP​

Answer 1

Answer:

Sn = 2n^2 +5n

we need nth term

so we know that the nth term of an A.P is given by

An = Sn- Sn-1

An = (2n^2+5n) - ( 2(n-1)^2 + 5(n-1))

= 4n + 3