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Module 4: Trigonometry

Topic A: Lessons 1-2: Special values and properties of trigonometric functions

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Trig values of special angles

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Graph of y=sin(x)

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Graph of y=tan(x)

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

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Sine & cosine identities: symmetry

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Tangent identities: symmetry

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Sine & cosine identities: periodicity

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Tangent identities: periodicity

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Practice

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

Topic A: Lessons 3-4: Addition and subtraction formulas

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Review of trig angle addition identities

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Using the cosine angle addition identity

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Using the cosine double-angle identity

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Proof of the sine angle addition identity

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Proof of the cosine angle addition identity

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Finding trig values using angle addition identities

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Practice

Using the trig angle addition identitiesGet 3 of 4 questions to level up!

Find trig values using angle addition identitiesGet 3 of 4 questions to level up!

Topic A: Lessons 5-6: Tangent lines and wave functions

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Lessons 5-6: No content yet

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Topic B: Trigonometry and triangles

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Lesson 7: No content yet

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Solving for a side with the law of sines

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Solving for an angle with the law of sines

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Proof of the law of sines

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Solving for a side with the law of cosines

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Solving for an angle with the law of cosines

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Proof of the law of cosines

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Trig word problem: stars

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Practice

Solve triangles using the law of sinesGet 3 of 4 questions to level up!

Solve triangles using the law of cosinesGet 3 of 4 questions to level up!

General triangle word problemsGet 3 of 4 questions to level up!

Topic C: Inverse trigonometric functions

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Lesson 11: No content yet

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Intro to arcsine

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Intro to arctangent

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Intro to arccosine

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Restricting domains of functions to make them invertible

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Domain & range of inverse tangent function

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Using inverse trig functions with a calculator

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Solving sinusoidal equations of the form sin(x)=d

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Solving cos(θ)=1 and cos(θ)=-1

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Trig word problem: solving for temperature

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Practice

Evaluate inverse trig functionsGet 3 of 4 questions to level up!

Solve sinusoidal equations (basic)Get 3 of 4 questions to level up!

Solve sinusoidal equationsGet 3 of 4 questions to level up!

Sinusoidal models word problemsGet 3 of 4 questions to level up!

About this unit

"This module revisits trigonometry that was introduced in Geometry and Algebra II, uniting and further expanding the ideas of right triangle trigonometry and the unit circle. New tools are introduced for solving geometric and modeling problems through the power of trigonometry. Students explore sine, cosine, and tangent functions and their periodicity, derive formulas for triangles that are not right, and study the graphs of trigonometric functions and their inverses." Eureka Math/EngageNY (c) 2015 GreatMinds.org