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Math Video Library Collection

Evaluating Trigonometric Functions

Video Summary:

In a right triangle ABC, with right angle C, the acute angles A and B are complementary. Since angles A and B are complementary, and sin A = cos B, the functions sine and cosine are called cofunctions. Similarly for secant and cosecant, and tangent and cotangent. A reference angle for an angle , written  , is the positive acute angle made by the terminal side of angle  and the x-axis.



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