Trigonometric Identities

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An Identity is an equation that is valid for all the possible values of the variables. For example (a+b)^2 = a^2 + 2ab +b^2 is an identity. It is valid for all the values of a and b. X^2 + 5X+6=0 is NOT an identity. It is only true for X=2 and X=3.

In this video, I go into a number of trigonometric identities, how to prove them and how to use them to solve problems.