http://1-formula.com/mathematical-formulas/basic-identities.html The basic Trigonometric Identities are presented with focus on the Pythagorean Identities. Identities pythagorean math trigonometry en-us Sat, 11 Oct 2008 21:26:50 GMT Sat, 2 Aug 2008 19:48:32 GMT www.1-formula.com www.1-formula.com http://1-formula.com/mathematical-formulas/basic-identities/the-additive-identity.html In mathematics the additive identity of a set which is equipped with the operation of addition is an element which, when added to any element x in the set, yields x. Sat, 2 Aug 2008 19:48:32 GMT http://1-formula.com/mathematical-formulas/basic-identities/the-additive-identity.html