Trigonometric Identities (Razones Trigonométricas)

Basically, if you study computer graphics you need to know some basic trigonometric identities, in order to understand some results, like 2D or 3D rotations. Here I provide a couple of links to lists of trigonometric identities:

• http://www.ucm.es/info/Geofis/practicas/trigonometria.htm
  
• http://www.sosmath.com/trig/Trig5/trig5/trig5.html
  
• http://en.wikipedia.org/wiki/Trigonometric_identity
  

And the most basic application, 2D rotation:

• Siggraph 2D rotation

If you can read Spanish I´ll recommend you to check this slides from the "Computer Graphics Fundamentals" course of the University Of Las Palmas de Gran Canaria.