JEE Mains · Maths · STD 11 - 8. sequence and series
If \(\tan \left(\frac{\pi}{9}\right), x, \tan \left(\frac{7 \pi}{18}\right)\) are in arithmetic progression and \(\tan \left(\frac{\pi}{9}\right), y, \tan \left(\frac{5 \pi}{18}\right)\) are also in arithmetic progression, then \(|x-2 y|\) is equal to:
- A \(0\)
- B \(3\)
- C \(4\)
- D \(1\)
Answer & Solution
Correct Answer
(A) \(0\)
Step-by-step Solution
Detailed explanation
\(x=\frac{1}{2}\left(\tan \frac{\pi}{9}+\tan \frac{7 \pi}{18}\right)\) and \(2 y=\tan \frac{\pi}{9}+\tan \frac{5 \pi}{18}\) so, \(x-2 y=\frac{1}{2}\left(\tan \frac{\pi}{9}+\tan \frac{7 \pi}{18}\right)\) \(-\left(\tan \frac{\pi}{9}+\tan \frac{5 \pi}{18}\right)\)…
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