Question 18
Calculate $$
\prod_{k=1}^{14} \cos \left(\frac{k \pi}{15}\right)
$$
\prod_{k=1}^{14} \cos \left(\frac{k \pi}{15}\right)
$$
MathNet 1986 — Part 01 Question 18
Math Olympiad Vault · MathNet 1986 — Part 01
Math Olympiad Vault · MathNet 1986 — Part 01