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Trigonometry

Right triangles & trigonometry

Ratios in right triangles: Right triangles & trigonometryIntroduction to the trigonometric ratios: Right triangles & trigonometrySolving for a side in a right triangle using the trigonometric ratios: Right triangles & trigonometry
Solving for an angle in a right triangle using the trigonometric ratios: Right triangles & trigonometrySine and cosine of complementary angles: Right triangles & trigonometryModeling with right triangles: Right triangles & trigonometryThe reciprocal trigonometric ratios: Right triangles & trigonometry

Trigonometric functions

Unit circle introduction: Trigonometric functionsRadians: Trigonometric functionsThe Pythagorean identity: Trigonometric functionsSpecial trigonometric values in the first quadrant: Trigonometric functionsTrigonometric values on the unit circle: Trigonometric functions
Graphs of sin(x), cos(x), and tan(x): Trigonometric functionsAmplitude, midline, and period: Trigonometric functionsTransforming sinusoidal graphs: Trigonometric functionsGraphing sinusoidal functions: Trigonometric functionsSinusoidal models: Trigonometric functionsLong live Tau: Trigonometric functions

Non-right triangles & trigonometry

Law of sines: Non-right triangles & trigonometryLaw of cosines: Non-right triangles & trigonometrySolving general triangles: Non-right triangles & trigonometry

Trigonometric equations and identities

Inverse trigonometric functions: Trigonometric equations and identitiesSinusoidal equations: Trigonometric equations and identitiesSinusoidal models: Trigonometric equations and identities
Angle addition identities: Trigonometric equations and identitiesUsing trigonometric identities: Trigonometric equations and identitiesChallenging trigonometry problems: Trigonometric equations and identities

Course challenge

Test your knowledge of the skills in this course. Have a test coming up? The Course challenge can help you understand what you need to review.

Review articles

Trig unit circle review
Laws of sines and cosines review
Pythagorean identity review
Midline, amplitude, and period review
Trigonometric ratios review
Community questions