Question

Exact value of cos 11pi/12
- using half angle identities

Answer 1

\(\Huge\color{black}{ \cos(\frac{θ}{2})=± \sqrt{\frac{1+ \cos θ}{2} } }\)

Answer 2

\(\Huge\color{black}{ \cos(\frac{330}{2})=± \sqrt{\frac{1+ \cos 330}{2} } }\)