Directions: Find the exact value using the appropriate identity

MATHEMATICS · Subjective · CBSE · Mathematics · Trigonometric Functions · Trigonometric Functions

Problem

Directions: Find the exact value using the appropriate identity. Use the given ratios. Simplify any radicals. Given

\cos A = \frac{1}{6}

and

270^\circ < A < 360^\circ

. Given

\sin B = -\frac{5}{6}

and

\pi < B < \frac{3\pi}{2}

. Find

\cos(2B)