10A-2i: Dynamic Geometry with Rotation and Secant Lines

This GeoGebra example demonstrates a dynamic geometric construction involving rotation, angles, segments, and secant lines. The main phenomenon is a line rotating around point A intersecting a fixed figure, producing adjustable secants and multiple associated angles. Core mathematical concepts include rotation, angle measurement, secant lines, and segment relationships. The construction uses commands such as Line, Rotate, Angle, and Segment, creating objects A, B, a, B', α, b, B'_1, β, c, C, γ, d, B'', δ, e, along with seven text labels (text1 to text7) and line f. This interactive setup allows users to explore how rotation affects the secant lines and angle relationships. It is suitable for middle school geometry or high school analytic geometry classes, serving as a visual aid for teachers or a self-exploration tool for students to understand rotation transformations, secant properties, and the interdependence of angles and segments.