Question

Write first four terms of the AP, when the first term a and the common difference d are given as follows: (i) a = 10, d = 10(ii) a = –2, d = 0​

Answer 1

Write first four terms of the AP, when the first term a and the common difference d are given as follows:

(i) a = 10, d = 10

(ii) a = -2, d = 0

Solution:

(i)Given:a = 10, d = 10

Let the series be a1, a2, a3, a4, a5 ...

a1 = a = 10

a2 = a1 + d = 10 + 10 = 20

a3 = a2 + d = 20 + 10 = 30

a4 = a3 + d = 30 + 10 = 40

a5 = a4 + d = 40 + 10 = 50

the series will be 10, 20, 30, 40, 50 ...

First four terms of this A.P. will be 10, 20, 30, and 40.

(ii)Given: a = -2, d = 0

Let the series be a1, a2, a3, a4 ...

a1 = a = -2

a2 = a1 + d = - 2 + 0 = -2

a3 = a2 + d = - 2 +0 = - 2

a4 = a3 + d = - 2+0 = - 2

the series will be -2,-2, -2,-2 ...

First four terms of this A.P. will be -2, -2,-2 and – 2.