# Trigonometric functions

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Practice
Radians & degreesGet 3 of 4 questions to level up!

## Trigonometric values of special angles

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Trig values of special angles
Practice
Trig values of special anglesGet 3 of 4 questions to level up!

## Trigonometric functions

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Unit circleThe trig functions & right triangle trig ratiosTrig unit circle review

## The graphs of sine, cosine, and tangent

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Graph of y=sin(x)Graph of y=tan(x)Intersection points of y=sin(x) and y=cos(x)

## Trigonometric identities

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Sine & cosine identities: symmetryTangent identities: symmetrySine & cosine identities: periodicityTangent identities: periodicityProof of the Pythagorean trig identityUsing the Pythagorean trig identityTrig challenge problem: cosine of angle-sum
Practice
Using the trig angle addition identitiesGet 3 of 4 questions to level up!
Use the Pythagorean identityGet 3 of 4 questions to level up!

## Trigonometric equations

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Solving sinusoidal equations of the form sin(x)=dSolving cos(θ)=1 and cos(θ)=-1
Practice
Solve sinusoidal equations (basic)Get 3 of 4 questions to level up!