Trigonometry: Free Online Course & Practice
Right-triangle trig, radians, the unit circle, graphs, identities, inverse trig, equations, laws of sines and cosines, vectors, and periodic modeling.
Algebra II-complete learners, precalculus prep, homeschool students, and adult refreshers7 units51 lessons2346 practice & quiz problemsFree
Not sure where to start? Take the free 15-minute placement check to pinpoint your gaps, then practice with instant feedback and worked solutions.
Take the free Trigonometry placement check Open the Trigonometry courseCourse outline
Right Triangle Trigonometry
- What Trigonometry Measures
- Opposite, Adjacent, and Hypotenuse
- Sine, Cosine, and Tangent Ratios
- Finding Missing Sides
- Finding Missing Angles with Inverse Trig
- Angles of Elevation and Depression
- Unit 1 Review and Quiz
Angles, Degrees, and Radians
- Degrees and Radians
- Arc Length and Sector Area
- Coterminal Angles
- Reference Angles
- Quadrants and Signs
- Unit 2 Review and Quiz
The Unit Circle
- Unit Circle Coordinates
- Special Angle Exact Values
- The Six Trig Functions
- Evaluating Trig Values in All Quadrants
- Reciprocal Trig Functions
- Unit Circle Fluency
- Unit 3 Review and Quiz
Graphs of Trig Functions
- Graphing Sine and Cosine
- Amplitude and Midline
- Period and Frequency
- Phase Shift
- Graphing Tangent
- Writing Trig Equations from Graph Features
- Unit 4 Review and Quiz
- Trigonometry Midterm Exam
Trig Identities
- Reciprocal and Quotient Identities
- Pythagorean Identities
- Simplifying Trig Expressions
- Verifying Trig Identities
- Sum and Difference Identities
- Double-Angle and Half-Angle Identities
- Unit 5 Review and Quiz
Inverse Trig and Equations
- Inverse Trig Functions
- Basic Sine and Cosine Equations
- Basic Tangent Equations
- Solving on a Given Interval
- Equations Using Identities
- General Solutions
- Unit 6 Review and Quiz
Applications of Trigonometry
- Law of Sines
- Law of Cosines
- The Ambiguous SSA Case
- Triangle Area with Trig
- Vectors and Components
- Periodic Modeling
- Cumulative Trig Modeling
- Unit 7 Review and Quiz
- Trigonometry Final Exam
Frequently asked questions
Is the Trigonometry course free?
Yes. The entire Trigonometry course — 51 lessons, 2346 practice and quiz problems, worked solutions, and the placement check — is free to use at ClearMath Academy.
What does the Trigonometry course cover?
Right-triangle trig, radians, the unit circle, graphs, identities, inverse trig, equations, laws of sines and cosines, vectors, and periodic modeling. It spans 7 units and 51 lessons, each with a worked example and practice problems with step-by-step solutions.
Who is Trigonometry for?
Trigonometry is aimed at algebra ii-complete learners, precalculus prep, homeschool students, and adult refreshers. You can take a free 15-minute placement check first to find exactly which lessons to start with.
How do I find my gaps in Trigonometry?
Take the free Trigonometry placement check. It pinpoints the specific skills you're missing in about 15 minutes and builds a practice plan focused on those gaps.