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The unit circle definition of the trigonometric functions
Learn about the ingenious way in which we define the trigonometric functions for any real number.
Sal shows how we can extend SOH CAH TOA so that we can define trig functions (sine, cosine, & tangent) for all real numbers.
Sal shows how, for acute angles, the two different definitions of the trigonometric values (SOH CAH TOA and the unit circle definition) result in the same values.