Improved Unit Circle Demo: Visualizing Trigonometric Functions

① This interactive GeoGebra example demonstrates the geometric representation of all six trigonometric functions (sine, cosine, tangent, cotangent, secant, cosecant) on the unit circle, showing how their values change as the angle varies. ② Core mathematical concepts include the unit circle definition of trigonometric functions, trigonometric line segments (sine line, cosine line, tangent line, etc.), angle measurement in degrees/radians, and periodicity. ③ Construction highlights: using GeoGebra commands such as Intersect, Circle, Point, Line, Ray, Angle, OrthogonalLine, and Segment to build the unit circle, radius, perpendiculars, tangents, and angle markers; key objects include center A, circle c, moving point C, angle θ, sine/cosine segments, tangent/cotangent/secant/cosecant segments, and positive/negative labels; the dynamic behavior is driven by dragging point C or using a slider. ④ Suitable for high school and introductory college students learning trigonometric definitions and graphs, as well as for teachers demonstrating the relationship between angles and trigonometric functions in classroom settings.