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The unit circle definition of sine, cosine, and tangent

Progress

Introduction to radians

The unit circle definition of sine, cosine, and tangent

The graphs of sine, cosine, and tangent

Basic trigonometric identities

Trigonometric values of special angles

The Pythagorean identity

Long live Tau

Unit test

10 questions

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Lessons

Introduction to radians The unit circle definition of sine, cosine, and tangent The graphs of sine, cosine, and tangent Basic trigonometric identities Trigonometric values of special angles The Pythagorean identity Long live Tau Unit test

Practice

Unit test

Introduction to radians

Learn

Intro to radians

Radians & degrees

Degrees to radians

Radians to degrees

Radian angles & quadrants

Practice

Radians & degrees

4 questions

Practice

The unit circle definition of sine, cosine, and tangent

Learn

The trig functions & right triangle trig ratios

Trig unit circle review

The graphs of sine, cosine, and tangent

Learn

Graph of y=sin(x)

Graph of y=tan(x)

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

Basic trigonometric identities

Learn

Sine & cosine identities: symmetry

Tangent identities: symmetry

Sine & cosine identities: periodicity

Tangent identities: periodicity

Trigonometric values of special angles

Learn

Trig values of special angles

Practice

Trig values of special angles

4 questions

Practice

The Pythagorean identity

Learn

Proof of the Pythagorean trig identity

Using the Pythagorean trig identity

Pythagorean identity review

Practice

Use the Pythagorean identity

4 questions

Practice

Learn

Pi is (still) wrong

Test your understanding of The unit circle definition of sine, cosine, and tangent with these 10 questions.

About this unit

Learn how the trigonometric ratios are extended to all real numbers using algebra. Start solving simple problems that involve this new definition of the trigonometric functions.