Question

The common difference of the A.P. is $\frac{1}{2q},\frac{1-2q}{2q},\frac{1-4q}{2q},...$is

(a) −1
(b) 1
(c) q
(d) 2q

Answer 1

Let a be the first term and d be the common difference.

The given A.P. is $\frac{1}{2q},\frac{1-2q}{2q},\frac{1-4q}{2q},...$

Common difference = d = Second term − First term
= $\frac{1-2q}{2q}-\frac{1}{2q}$
= $\frac{-2q}{2q}=-1$

Hence, the correct option is (a).