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Cofunction identities
- Intro Lesson8:56
- Lesson: 14:33
- Lesson: 2a3:44
- Lesson: 2b2:24
- Lesson: 2c3:44
Cofunction identities
Lessons
Cofunction Identities: Basically, we need the sum of the left and right brackets to be 90° or 2π
sin(2π−θ)=cos(θ)
sin(θ)=cos(2π−θ)
tan(2π−θ)=cot(θ)
tan(θ)=cot(2π−θ)
sec(2π−θ)=csc(θ)
sec(θ)=csc(2π−θ)
sin(2π−θ)=cos(θ)
sin(θ)=cos(2π−θ)
tan(2π−θ)=cot(θ)
tan(θ)=cot(2π−θ)
sec(2π−θ)=csc(θ)
sec(θ)=csc(2π−θ)
- IntroductionWhat are cofunction identities?
• Relationships between trigonometric functions and their cofunctions - 1.Write the following in terms of its cofunction:
■ sin(23)
■ cos(47)
■ tan(6π)
■ csc(6π) - 2.Solve for xa)sin(x−4π)=cos(12π+3x)b)cot(8∘+x)=tan(4x−3∘)c)csc(3x+5π)=sec(2x−10π)