Find the nth term of the following A.P.'s:

1.1, 2.1, 3.1, 4.1, ...

Formula Used.

d_n = a_{n + 1} – a_n

a_n = a + (n–1)d

In the above sequence,

a = 1.1;

d₁ = a₂–a₁ = 2.1–1.1 = 1

d₂ = a₃–a₂ = 3.1–2.1 = 1

d₃ = a₄–a₃ = 4.1–3.1 = 1

The difference in sequence is same and comes to be (1).

∴ The above sequence is A.P

The n^th term of A.P is a_n = a + (n–1)d

a_n = a + (n–1)d = 1.1 + (n–1)(1)

= 1.1 + n–1

= 0.1 + n