Question

Find an exact value.

sin 15°

Answer 1

A similar identity exists here
\[\Large \sin(\color{red}\alpha-\color{blue}\beta) = \sin(\color{red}\alpha)\cos(\color{blue}\beta) - \cos(\color{red}\alpha) \sin (\color{blue}\beta)\]

And, of course,
\[\Large 15^o = \color{red}{45^o}- \color{blue}{30^o}\]