Cosine of Integer Multiple of Argument/Formulation 5/Examples

Examples of Use of Cosine of Integer Multiple of Argument/Formulation 5

Cosine of Quintuple Angle

$\cos 5 \theta = \cos \theta + 2 \cos \theta \paren {\cos 4 \theta - \cos 2 \theta}$

Cosine of Sextuple Angle

$\map \cos {6 \theta } = -1 + 2 \cos \theta \paren {\cos 5 \theta - \cos 3 \theta + \cos \theta }$