Write first four of the terms of the A.P., when the first term a and the common difference a are given as follows :

(i) a = 10, d = 10

(ii) a = -2, d = 0

(iii) a = 4, d = -3

(iv) a = $\dfrac{1}{2}$, d = $-\dfrac{1}{6}$

Which of the following lists of numbers form an A.P. ? If they form an A.P., find the common difference d and write the next three terms:

(i) 4, 10, 16, 22, ….

(ii) -2, 2, -2, 2, ….

(iii) 2, 4, 8, 16, ….

(iv) $2, \dfrac{5}{2}, 3, \dfrac{7}{2}, ….$

(v) -10, -6, -2, 2, …

(vi) 1², 3², 5², 7², ….

Find the A.P. whose nth term is 7 - 3n. Also find the 20th term.

Find the indicated terms in each of the following A.P.s :

(i) 1, 6, 11, 16, ….; a₂₀

(ii) -4, -7, -10, -13, …., a₂₅, a_n