Examples, solutions, videos and lessons to help High School students learn how to
explain and use the relationship between the sine and cosine of
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.
Sine and Cosine Relationships of Complementary angles
Sine and Cosine of complementary angles are congruent.
Complementary Angle Theorem
Complementary Angles with Trig Ratios
Complementary angles in trigonometry.
Complementary angles in trigonometry
Cofunctions of Complementary Angles
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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