Curve Stitching: Constructing a Parabola from Straight Lines

① This example demonstrates how to construct a parabola by stitching together a series of straight line segments, visually revealing the envelope of lines that forms a curved shape. ② Core mathematical concepts include parabolas, straight lines, sequences, rational numbers, and function graphing, with emphasis on parametric construction and locus ideas. ③ Construction highlights: using GeoGebra's Sequence command to generate point sets and line segments, defining parameters n and a, and utilizing lists list1 through list5, along with objects A, b, c, and text1, to create a dynamic line-stitching effect that outlines the parabola. ④ Suitable for middle or high school mathematics classrooms, this activity helps students understand quadratic functions, line envelopes, and the basics of sequences and iteration, and can serve as an exploratory learning resource.