Which of the following are APs ? If they form an AP, find the common difference d and write three more terms.

(i) 2, 4, 8, 16, ….

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

(iii) -1.2, -3.2, -5.2, -7.2, ……..

(iv) -10, -6, -2, 2, ………

(v) 3, 3 + $\sqrt{2}, 3 + 2\sqrt{2}, 3 + 3\sqrt{2}$, ……….

(vi) 0.2, 0.22, 0.222, 0.2222, ……….

(vii) 0, -4, -8, -12, ……..

(viii) $-\dfrac{1}{2}, -\dfrac{1}{2}, -\dfrac{1}{2}, -\dfrac{1}{2}, ………..$

(ix) 1, 3, 9, 27, ……..

(x) a, 2a, 3a, 4a, ……….

(xi) a, a², a³, a⁴, ………..

(xii) $\sqrt{2}, \sqrt{8}, \sqrt{18}, \sqrt{32},$ ………..

(xiii) $\sqrt{3}, \sqrt{6}, \sqrt{9}, \sqrt{12},$ ………..

(xiv) 1², 3², 5², 7², ……

(xv) 1², 5², 7², 73, ……

Fill in the blanks in the following table, given that a is the first term, d the common difference and a_n the nth term of the AP :

Choose the correct choice in the following and justify :

11th term of the A.P. : -3, $-\dfrac{1}{2}$, 2, ….., is

1. 28

2. 22

3. -38

4. $-48\dfrac{1}{2}$

In the following APs, find the missing terms :

(i) 2, ……, 26.

(ii) ……, 13, ……, 3.

(iii) 5, ……, ……., $9\dfrac{1}{2}$

(iv) -4, ……, ….., ….., ……, 6

(v) ……, 38, ……, ….., ……, -22