TrigFactorList

TrigFactorList[expr] factors trigonometric functions in expr, yielding a list of lists containing trigonometric monomials and exponents.

Examples

TrigFactorList[Sin[x]^2]
(* {{Sin[x], 2}} *)

TrigFactorList[Sin[x] Cos[x]]
(* {{Cos[x], 1}, {Sin[x], 1}} *)

Please visit the official Wolfram Language Reference for more details.