Question

The value of cos 20${}^{\circ }$ cos 40${}^{\circ }$ cos 60${}^{\circ }$ cos 80${}^{\circ }$ is equal to

• A. $\frac{3}{8}$
• B. $\frac{1}{16}$
• C. $\frac{1}{8}$
• D. $\frac{3}{16}$

Answer 1

Answer: (A)

Correct answer is (a) $\frac{3}{8}$