达兰贝尔球与抛物线

达兰贝尔球与抛物线
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2020-02-17 11:18
①本范例演示达兰贝尔球如何解释抛物线、椭圆和双曲线为何是圆锥曲线;②涉及核心概念:圆锥曲线、达兰贝尔球、几何定义、圆锥截面;③作图要点:使用 GeoGebra 命令如 InfiniteCone(无限圆锥)、Rotate(旋转)、IntersectPath(路径相交)、Circle(圆)、Sphere(球)等构建几何模型;④适合高中及以上学生及需要深入理解圆锥曲线几何本质的教育者。

GeoGebra 命令及参数

  1. InfiniteCone((0, 0, 0), zAxis, α) → a
  2. Axes(a) → d, e, f
  3. Rotate(f, (-α), yAxis) → lineOA
  4. Point(lineOA) → A
  5. Rotate(f, α, yAxis) → f'
  6. Point(f') → B
  7. Plane(A, B_1, B) → b
  8. IntersectPath(b, a) → EllipseHyperbola
  9. Axes(EllipseHyperbola) → i, j
  10. AngularBisector(f', i) → b2, b1
  11. Center(a) → O
  12. Vector(O, B) → vOB
  13. Angle(Vector[A, B], Vector[A, O]) → β
  14. Vector(O, A) → vOA
  15. Rotate(vOA, β / 2, A, k) → vOA'
  16. Angle(Vector[B, A], Vector[O, B]) → α1
  17. Rotate(vOB, α1 / 2, B, k) → vOB'
  18. Ray(B, B') → g
  19. Intersect(f, b1) → CenterSphere1
  20. OrthogonalLine(CenterSphere1, i, k) → h
  21. Intersect(i, h) → H
  22. Circle(CenterSphere1, H, k) → p
  23. Sphere(CenterSphere1, H) → l
  24. Ray(A, A') → m
  25. Intersect(f, b2) → CenterSphere2
  26. OrthogonalLine(CenterSphere2, i, k) → n
  27. Intersect(i, n) → M
  28. Circle(CenterSphere2, M, k) → s
  29. Point(EllipseHyperbola) → P
  30. Line(O, P) → a_1
  31. Segment(M, P) → b_1
  32. Segment(P, H) → e_1
  33. Sphere(CenterSphere2, M) → l'
  34. OrthogonalLine(CenterSphere2, lineOA, k) → q
  35. OrthogonalLine(CenterSphere1, lineOA, k) → r
  36. Intersect(lineOA, r) → C
  37. Intersect(q, lineOA) → D
  38. Circle(f, C) → tangentCircle1
  39. Circle(f, D) → tangentCircle2
  40. Line(O, P) → lineOP
  41. Intersect(lineOP, tangentCircle2) → TangencyP2,
  42. Intersect(lineOP, tangentCircle1) → TangencyP1,
  43. Segment(P, TangencyP1) → PtoTangent1
  44. Segment(TangencyP2, P) → PtoTangent2
  45. Segment(O, TangencyP2) → coneEdge
  46. Tangent(A, EllipseHyperbola) → t,
  47. Plane(t, lineOA) → tangentToConePlane
  48. Plane(B, tangentToConePlane) → planeForParabola
  49. IntersectPath(planeForParabola, a) → Parabola
  50. Intersect(f, Parabola) → E,
  51. Intersect(f, planeForParabola) → F_1
  52. Line(B, F_1) → c
  53. AngularBisector(f', c) → f_1, g_1
  54. Intersect(g_1, f) → C_{SphereForParabola}
  55. OrthogonalLine(C_{SphereForParabola}, c, space) → h_1
  56. Intersect(h_1, c) → F
  57. Sphere(C_{SphereForParabola}, F) → o
  58. Point(Parabola) → G
  59. Segment(F, G) → i_1
  60. Intersect(f', o) → I, J
  61. Circle(f, I) → c_1
  62. Sphere(B, F) → u
  63. Intersect(c, u) → K, L
  64. OrthogonalPlane(K, c) → p_1
  65. IntersectPath(p_1, planeForParabola) → directrix
  66. OrthogonalLine(G, p_1) → k_1
  67. Intersect(directrix, Parabola) → N, T
  68. Intersect(directrix, k_1) → Q
  69. Segment(G, O) → l_1
  70. Intersect(l_1, c_1, 1) → R
  71. Plane(c_1) → tangentCirclePlaneForParabola
  72. OrthogonalLine(G, tangentCirclePlaneForParabola) → m_1
  73. Intersect(m_1, tangentCirclePlaneForParabola) → S
  74. Angle(S, G, R) → γ
  75. Angle(Q, G, S) → δ
  76. Segment(G, R) → j_1
  77. Segment(Q, G) → n_1
  78. Segment(Q, S) → q_1
  79. Segment(S, R) → r_1
  80. Angle(G, S, Q) → ε
  81. Angle(R, S, G) → ζ
  82. If(checkBoxEllHyp, checkBoxParabola + (0 * z) = false) → p_2
  83. If(checkBoxEllHyp, checkBoxParabola + (0 * z) = false) → q_2
  84. If(checkBoxEllHyp, checkBoxParabola + (0 * z) = false) → r_2
  85. If(checkBoxEllHyp, checkBoxParabola + (0 * z) = false) → p_3
  86. If(checkBoxEllHyp, checkBoxParabola + (0 * z) = false) → q_3
  87. If(checkBoxEllHyp, checkBoxParabola + (0 * z) = false) → r_3
  88. If(checkBoxEllHyp, checkBoxParabola + (0 * z) = false) → p_4
  89. If(checkBoxEllHyp, checkBoxParabola + (0 * z) = false) → q_4
  90. If(checkBoxEllHyp, checkBoxParabola + (0 * z) = false) → r_4
  91. If(checkBoxEllHyp, checkBoxParabola + (0 * z) = false) → p_5
  92. If(checkBoxEllHyp, checkBoxParabola + (0 * z) = false) → q_5
  93. Angle(G, Q, K) → η

AI 绘图提示语参考

画一个圆锥,在其上生成一条旋转线,形成截面曲线。展示两个Dandelin球,一个与截面曲线相切于两个点,另一个与截面曲线相切于一个点。标出圆锥的顶点、截面曲线上的点、切点以及Dandelin球的中心,并画出与截面曲线相切的球面。最后,连接顶点与截面曲线上的点,形成一条直线。
以上提示语为根据原始绘图命令整理而来,仅供参考。