Deriving trigonometric identities, no unit circles Oct 1, 2017 22:40:37 GMT Quote Select PostDeselect PostLink to PostMemberGive GiftBack to Top Post by Tiago on Oct 1, 2017 22:40:37 GMT You can learn how to derive fundamental trigonometric identities without the use of unit circles by accessing this link... mathsvideos.net/deriving-trigonometric-identities-without-the-use-of-unit-circles/