Question

The nth term of an A.P., the sum of whose n terms is S_n, is 

A. S_n + S_n–1 

B. S_n – S_n–1 

C. S_n + S_{n + 1} 

D. S_n – S_{n + 1}

Answer 1

The sum of n terms of an A.P is given by S_n 

S_n = \(\frac{n}{2}\)(2a + (n–1) d)

 If the sum of n terms is given that is S_n is given then the nth term is given by the formula 

T_n = S_n– S_n–1 Where S_n–1 is sum of the (n–1)^th term of the A.P.