Section of Triangular Pyramids

①This example demonstrates how to construct a triangular pyramid (tetrahedron) in GeoGebra and generate a cross-section by intersecting a plane with the pyramid, visually revealing the shape and position of the section in solid geometry. ②Core mathematical concepts include pyramids, cross-sections, intersection of a plane with a polyhedron, and spatial transformations such as translation and rotation; auxiliary tools like arithmetic mean, trigonometric functions, and matrices are also involved in the construction. ③Construction highlights: from the summary, commands such as Polygon (creating base polygon), PointIn (point on face), Translate and Rotate (spatial movement and rotation), Pyramid (generating the pyramid), Plane (defining the cutting plane), IntersectPath (computing the intersection path), and OrthogonalLine (perpendicular lines) are used; objects include faces (face1-3), edges (edge1-3), and text labels (text1-9) for annotations. ④Suitable for high school or early college students learning solid geometry, allowing dynamic manipulation to observe how the section changes, enhancing spatial visualization and geometric reasoning; also useful for teacher demonstrations or student self-exploration.