Sin and Cos of Complementary Angles
Common Core (Geometry)
Common Core for Mathematics
Examples, solutions, videos and lessons to help High School students learn how to explain and use the relationship between the sine and cosine of complementary angles.
sin θ = cos(90 - θ)Common Core: HSG-SRT.C.7
The following diagram shows the Complementary Angle Theorem. Scroll down the page for more examples and solutions using the Complementary Angle Theorem.
Cofunctions
Sine and Cosine of complementary angles are congruent.
Complementary angles in trigonometry.
This video explains the cofunction identities and how to determine cofunctions given a function value. Most cofunction values are verified on a calculator.
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