Math · Level 4

4.2 Trigonometry

Ramp up on the fundamentals of trigonometry as you master identities, polar graphic, and solving triangles.

Defining Angles

Trigonometric Ratios

The Unit Circle

Solving Right Triangles

Solving for Angles

Law of Cosines

Law of Sines

Ambiguous Cases

Trigonometry Graphs

Other Trigonometric Graphs

Trigonometric Graph Problem Solving

Trigonometric Graph Symmetry

Inverse Trigonometry

Polar Coordinates

Roses, Cardioids and Limaçon

Function Transformations

Reciprocal and Quotient Identities

Triangle Identities

Sum and Difference Identities

Double- and Half-Angle Identities


Course description

This course will teach you all of the fundamentals of trigonometry, starting from square one: the basic idea of similar right triangles. In the first sequences in this course, you'll learn the definitions of the most common trigonometric functions from both a geometric and algebraic perspective. In this course, you'll master trigonometry by solving challenging problems and interacting with animated graphs, not by relying on rote memorization. Additionally, you'll learn how to apply trigonometry in the contexts of measuring and manipulating sound waves and creating complex, artistic designs using polar graphing. By the end of this course, you’ll be a master at solving triangles, graphing trig functions in both Cartesian and polar coordinates, and applying trigonometric identities.


Topics covered

  • Cosine
  • Inverse Trig Functions
  • Law of Cosines
  • Law of Sines
  • Polar Coordinates
  • Sine
  • Tangent
  • The Unit Circle
  • Trigonometric Identities
  • Wave Frequency

Prerequisites and next steps

You should know the content up through our Algebra II course.

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Math · Level 5

5.1 Calculus in a Nutshell

Investigate the central ideas of calculus and learn how to put them to use.

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