WBJEE · Maths · Trigonometric Ratios & Identities
The value of \((1+\cos \pi / 6)(1+\cos \pi / 3)(1+\cos 2 \pi / 3)(1+\cos 7 \pi / 6)\) is
- A \(\frac{3}{16}\)
- B \(\frac{3}{8}\)
- C \(\frac{3}{4}\)
- D \(\frac{1}{2}\)
Answer & Solution
Correct Answer
(A) \(\frac{3}{16}\)
Step-by-step Solution
Detailed explanation
Hints : \(\left(1+\cos \frac{\pi}{6}\right)\left(1+\cos \frac{\pi}{3}\right)\left(1+\cos \frac{2 \pi}{3}\right)\left(1+\cos \frac{7 \pi}{6}\right)\)…
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