Angle Bisectors Construction and Properties

① This GeoGebra example demonstrates the construction of angle bisectors within a triangle, showing how each bisector divides its vertex angle into two equal smaller angles. ② Core mathematical concepts include the definition of an angle bisector, the concurrency of internal angle bisectors at the incenter (if extended), and the angle bisector theorem (points on the bisector are equidistant from the two sides). ③ Construction details: using the Segment command to draw triangle sides, Polygon to form the triangle, and points A, B, C with sides a, b, c to construct the bisectors (objects a_1, b); dragging vertices dynamically verifies that the bisectors maintain their property as the triangle changes. ④ Suitable for middle school geometry lessons or high school review, helping students understand compass-and-straightedge construction of angle bisectors and dynamically verify their properties, also useful as an interactive teaching resource.