Unit Circle and Trigonometric Functions by Michael PArk

① This example demonstrates the geometric meaning of trigonometric functions (sine, cosine, tangent) using a dynamic point on the unit circle. ② Core mathematical concepts include the unit circle definition, trigonometric ratios, angle-radian conversion, and the generation of function graphs from circular motion. ③ Construction highlights: The GeoGebra commands Circle, Point, and CircleArc are used to create the unit circle, a movable point P, and arcs; objects A, c, B, C, d, P, Q, f, g, a, b, and text1 are linked to show projections and values. ④ Suitable for high school trigonometry lessons, college precalculus review, and interactive teacher demonstrations, helping learners grasp periodicity and symmetry through visual exploration.