Question

If Sn=n(n+1)/2 , find first two tearms of ap

Answer 1

Answer:

The first two terms of AP = 1,2.

Step-by-step explanation:

Sn = n(n+1)/2

A1 = 1(1+1)/2 = 2/2 = 1

S2 = 2(2+1)/2 = 3

But, S2 = A1+A2

=> A2 = 2

Hope it helps.....