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Question
If k, 2k − 1 and 2k + 1 are three consecutive terms of an A.P., the value of k is
Options
−2
3
- 3
6
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Solution
Since, k, 2k − 1 and 2k + 1 are three consecutive terms of an A.P.
Then, Second term − First term = Third term − Second term = d (common difference)
⇒ 2k − 1 − k = 2k + 1 − (2k − 1)
⇒ k − 1 = 2k + 1 − 2k + 1
⇒ k − 1 = 2
⇒ k = 2 + 1
⇒ k = 3
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