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Question
The common difference of the A.P. \[\frac{1}{2b}, \frac{1 - 6b}{2b}, \frac{1 - 12b}{2b}, . . .\] is
Options
2b
−2b
3
- 3
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Solution
Let a be the first term and d be the common difference.
The given A.P. is \[\frac{1}{2b}, \frac{1 - 6b}{2b}, \frac{1 - 12b}{2b}, . . .\]
Common difference = d = Second term − First term
= \[\frac{1 - 6b}{2b} - \frac{1}{2b}\]
= \[\frac{- 6b}{2b} = - 3\]
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