WBJEE · Maths · Trigonometric Equations
The value of \(\tan \frac{\pi}{5}+2 \tan \frac{2 \pi}{5}+4 \cot \frac{4 \pi}{5}\) is
- A \(\cot \frac{\pi}{5}\)
- B \(\cot \frac{2 \pi}{5}\)
- C \(\cot \frac{4 \pi}{5}\)
- D \(\cot \frac{3 \pi}{5}\)
Answer & Solution
Correct Answer
(A) \(\cot \frac{\pi}{5}\)
Step-by-step Solution
Detailed explanation
\(\tan \frac{\pi}{5}+2 \tan \frac{2 \pi}{5}+4 \cot \frac{4 \pi}{5}\) \(=\frac{\sin \frac{\pi}{5}}{\cos \frac{\pi}{5}}+2 \frac{\sin \frac{2 \pi}{5}}{\cos \frac{2 \pi}{5}}+4 \frac{\cos \frac{4 \pi}{5}}{\sin \frac{4 \pi}{5}}\)…
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