Question

if sn , the sum of First n terms of an ap is given by sn = (3n²-4n) , then find the nth term

Answer 1

Hiii friend,

Sn = (3N²-4N)------------(1)


Replacing n by (n-1) in equation (1) , we get

Sn-1 = 3(N-1)² - 4 × (N-1)

=> Sn-1 = 3(N²-2N+1) - 4N+4

=> Sn-1 = 3N²-6N+3-4N+4

=> Sn-1 = 3N²-10N+7


Therefore,


Tn = (Sn-Sn-1) => (3N²-4N)-(3N²-10N+7)

Tn = 3N²-4N-3N²+10N-7 = (6N-7).



Therefore,


Nth term , Tn = (6N-7)



HOPE IT WILL HELP YOU...... :-)

Answer 2

Step-by-step explanation:

Hii mate here is your answer