Wolfram Demonstrations Projecthttp://demonstrations.wolfram.com/An Open Resource of Interactive Mathematica VisualizationsCopyright 2009 Wolfram Demonstrations Project & ContributorsCofunction Identities for Sine and Cosinehttp://demonstrations.wolfram.com/CofunctionIdentitiesForSineAndCosine/]]>http://demonstrations.wolfram.com/CofunctionIdentitiesForSineAndCosine/