Trigonometric functions on the circle

Build a geometric understanding of trigonometric functions on the circle. This precalculus practice set connects sine and cosine to coordinates, extends right-triangle ratios to general angles, and develops tangent, cotangent, secant and cosecant from a nonzero terminal point.

Progress from reading a unit-circle diagram to reasoning about axis angles, undefined denominators, radius normalization and circular-motion models. Single-select and multiselect questions include worked explanations and address common coordinate and reciprocal errors. Familiarity with Cartesian coordinates, the Pythagorean theorem and basic triangle ratios is recommended.