三角柱体的截面探究

三角柱体的截面探究
几何画板及绘图内容加载中,请稍等……
2019-06-29 06:57
①本范例演示如何通过不同平面截取三角柱体,观察其截面形状与性质;②涉及的核心数学概念包括立体几何、截面几何、几何变换;③作图要点运用了Polygon(多边形)、PointIn(点在对象内)、Translate(平移)、Rotate(旋转)、Prism(棱柱)、Plane(平面)、IntersectPath(路径相交)、OrthogonalLine(垂线);④适合高中立体几何教学或学生自主探究几何截面问题。

GeoGebra 命令及参数

  1. Polygon(B + (-2, -2), B + (2, -2), B + (2, 2), B + (-2, 2)) → poly3, e, f, g, i
  2. PointIn(poly3) → C
  3. Translate((0, 0, 0), Vector[B, C]) → A
  4. Polygon(A + (-4, -4), A + (4, -4), A + (4, 4), A + (-4, 4)) → poly1, a, b, c, d
  5. Rotate(Rotate[Translate[poly1, Vector[A, A + (0, 0, h)]], (90° * s), A + (0, 0, h), yAxis], (90° * t), A, zAxis) → poly2
  6. Rotate(D, 120°, (0, 0, 0)) → E
  7. Polygon(D, E, 3, xOyPlane) → poly4, j, k, l, F
  8. Prism(poly4, D + (0, 0, 4)) → m, M, edge4, edge5, edge6, N, face1, face2, face3, face4, edge1, edge2, edge3
  9. PointIn(poly2) → G
  10. PointIn(poly2) → H
  11. PointIn(poly2) → I
  12. Plane(G, I, H) → n
  13. IntersectPath(n, m) → poly6, poly5, r, a_1, b_1, c_1, K, L_1, O, P, J, L, p, q
  14. Rotate(m, 0, zAxis) → m'
  15. Rotate(m, 0, zAxis) → m'_1
  16. OrthogonalLine(A, n) → d_1