Cosine Chain

Geometry Level 2

\[\large\cos\left(\dfrac{2\pi}{15}\right)\cos\left(\dfrac{4\pi}{15}\right)\cos\left(\dfrac{8\pi}{15}\right)\cos\left(\dfrac{14\pi}{15}\right)=\dfrac{A}{B}\]

If \(A,B\) are co-prime integers , find \(B - A\).