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Trigonometric Functions: Unit Circle. Unit Circle. The unit circle is a circle whose radius is 1 and whose center is at the origin of a rectangular coordinate system. Let t be a real number and let P = ( x,y ) be the point on the unit circle that corresponds to t. Trig Functions.
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Unit Circle The unit circle is a circle whose radius is 1 and whose center is at the origin of a rectangular coordinate system
Let t be a real number and let P = (x,y) be the point on the unit circle that corresponds to t
Trig Functions There are six trigonometric functions
Reference Angles Let α (Greek alpha) be an acute angle in standard position. For example α= 20° Notice that the terminal ray of α= 20° 180°- α= 160° are symmetric In the y axis. The angle α is called a reference angle.
General Info for Reference angles In general, the acute angle α is the reference angle for the angles, 180°- α, 180°+α, 360°-α Example: Express sin 695° in terms of a reference angle.