 # Evaluating Sine and Cosine of Special Acute Angles

Videos, worksheets, solutions, and activities to help Algebra 2 students learn how to evaluate sine and cosine of special acute angles (given in radians).

Evaluating Sine and Cosine at Special Acute Angles :
If you want to make your math life incredibly easier, memorize the sine and cosine values for pi/3, pi/4, and pi/6, as well as 0, pi/2, and pi. These values constantly reappear throughout Trigonometry and pre-Calculus problems and proofs. When evaluating sine, it is also useful to memorize the conversion from radians to degrees for these values; for example, to remember that pi/6 is equivalent to 30°.
PM12 - 3.4 Special Angles (Sine & Cosine) - part 1
PM12 - 3.4 Special Angles (Sine & Cosine) - part 2

Finding the special trig ratios for the quadrantal angles and 30, 45, and 60 degrees (radians as well)

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