Definizione di Circonferenza Unitaria delle Funzioni Trigonometriche

Help us caption and translate this video on Amara.org: http://www.amara.org/en/v/B2v1/ Esercizi: http://www.khanacademy.org/exercise/unit_circle Traduzione in Italiano del video Unit Circle Definition of Trig Functions http://www.youtube.com/watch?feature=player_embedded&v=ZffZvSH285c http://www.khanacademy.org/video/unit-circle-definition-of-trig-functions?playlist=Trigonometry Help us caption & translate this video! http://amara.org/v/B2v1/