sin(a + b) & cos(a + b) - Discovery

Directions are given in the applet below.
Use your results to write 2 new trigonometric identities from what you now see. [br][b][color=#c51414]After doing so, go to the following applet: http://tube.geogebra.org/m/1651617[/color][/b]

Information: sin(a + b) & cos(a + b) - Discovery