More Lessons for Trigonometry
In this lesson, we will look at co-function identities.
What are the Co-function Identities?
A function f is cofunction of a function g if f(A) = g(B) when A and B are complementary angles.
sin A = cos(90° - A)
cos A = sin(90° - A)
sin A = cos B, if A + B = 90°
sec A = csc(90° - A)
csc A = sec(90° - A)
sec A = csc B, if A + B = 90°
tan A = cot(90° - A)
cot A = tan(90° - A)
tan A = cot B, if A + B = 90°
This video explains the cofunction identities and how to determine cofunctions given a function value. What is a cofunction. Finding the cofunction. Using the cofunction relationship
Cofunction Identities Trig
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