Theorem: Trigonometric Identities for Argument Offsets The sine, cosine, tangent and cotangent have the following properties: 2π+θ2π−θπ+θπ−θ23π+θ23π−θsincosθcosθ−sinθsinθ−cosθ−cosθcos−sinθsinθ−cosθ−cosθsinθ−sinθtan−cotθcotθtanθ−tanθ−cotθcotθcot−tanθtanθcotθ−cotθ−tanθtanθ PROOF TODO