Dini Surface Parametric Construction

This example demonstrates the classic Dini Surface from differential geometry, a helical developable surface formed by rotating a line around a helix while maintaining a constant tilt angle. Key mathematical concepts include: parametric representation of surfaces, principal curvature calculation, and geometric relationships between helical and asymptotic lines. Construction details: Using GeoGebra's Surface command with parameters a (helix radius), b (pitch coefficient), and c (tilt angle) to construct a 3D parametric surface, visually showing the continuous transformation from planar spiral to twisted shape. This example is suitable for university-level differential geometry courses and can serve as a training resource for parametric equations and spatial visualization in high school mathematics extension projects.