三角形中心

三角形中心
几何画板及绘图内容加载中,请稍等……
2019-03-27 16:36
①本范例演示了如何通过 GeoGebra 绘制三角形的中心点;②涉及的核心数学概念包括解析几何、几何作图、线段中点、角平分线、垂线等;③作图要点——从下方『构造摘要』提炼用到了 Polygon(多边形)、LineBisector(角平分线)、Intersect(交点)、OrthogonalLine(垂线)、AngularBisector(角平分线)、Midpoint(中点)、Line(直线)、Circle(圆)、Center(中心)、Segment(线段)等 GeoGebra 命令/对象;④适合高中数学教学或几何学习,帮助理解三角形几何性质。

GeoGebra 命令及参数

  1. Polygon(A, B, C) → t1, c, a, b
  2. LineBisector(b) → f
  3. LineBisector(a) → g
  4. LineBisector(c) → h
  5. Intersect(f, h) → O
  6. OrthogonalLine(A, a) → i
  7. OrthogonalLine(B, b) → j
  8. OrthogonalLine(C, c) → k
  9. Intersect(i, j) → H
  10. AngularBisector(A, B, C) → l
  11. AngularBisector(B, C, A) → m
  12. AngularBisector(C, A, B) → n
  13. Intersect(l, m) → I_1
  14. Midpoint(A, C) → M_3
  15. Midpoint(B, C) → M_2
  16. Midpoint(A, B) → M_1
  17. Line(B, M_3) → p
  18. Line(C, M_1) → q
  19. Line(A, M_2) → r
  20. Intersect(p, q) → G
  21. Polygon(B, C, 3) → poly1, s, t, d, J
  22. Polygon(A, B, 3) → poly2, e, f_1, g_1, K
  23. Polygon(C, A, 3) → poly3, h_1, i_1, j_1, L
  24. Circle(K, A, B) → c_1
  25. Circle(J, B, C) → d_1
  26. Circle(A, C, L) → e_1
  27. Intersect(c_1, d_1, 2) → F
  28. Circle(M_1, M_2, M_3) → k_1
  29. Center(k_1) → N
  30. OrthogonalLine(I_1, c) → l_1
  31. Intersect(l_1, c) → D
  32. Circle(I_1, D) → p_1
  33. Intersect(p_1, k_1) → F_4, , ,
  34. Circle(B, A, C) → q_1
  35. Line(O, H) → E
  36. Segment(I_1, A) → m_1
  37. OrthogonalLine(A, m_1) → n_1
  38. Segment(I_1, C) → r_1
  39. OrthogonalLine(C, r_1) → s_1
  40. Intersect(m_1, r_1) → I
  41. Intersect(n_1, s_1) → P
  42. Segment(I, B) → t_1
  43. OrthogonalLine(B, t_1) → a_1
  44. Intersect(n_1, a_1) → Q
  45. Intersect(s_1, a_1) → R
  46. OrthogonalLine(Q, c) → b_1
  47. OrthogonalLine(R, a) → f_2
  48. OrthogonalLine(P, b) → g_2
  49. Intersect(b_1, c) → S
  50. Intersect(f_2, a) → T
  51. Intersect(g_2, b) → U
  52. Circle(Q, S) → c_2
  53. Circle(R, T) → d_2
  54. Circle(P, U) → e_2
  55. Line(H, O) → h_2
  56. Line(B, A) → i_2
  57. Line(B, C) → j_2
  58. Line(A, C) → k_2
  59. Intersect(j_2, a) → V
  60. Intersect(j_2, a) → W
  61. Intersect(j_2, a) → Z
  62. Intersect(j_2, a) → A_1
  63. Intersect(i_2, c) → B_1
  64. Intersect(i_2, c) → C_1
  65. Intersect(i_2, c) → D_1
  66. Intersect(i_2, c) → E_1
  67. Intersect(i_2, c) → F_5
  68. Intersect(i_2, c) → G_1
  69. Intersect(c_2, i_2) → H_1, T_C
  70. Intersect(k_2, b) → J_1
  71. Intersect(e_2, k_2) → T_B,
  72. Intersect(d_2, j_2) → T_A,
  73. Segment(T_A, A) → l_2
  74. Segment(C, T_C) → m_2
  75. Segment(B, T_B) → n_2
  76. Intersect(l_2, m_2) → K_1
  77. Intersect(c_2, k_1) → F_1, , ,
  78. Intersect(d_2, k_1) → F_2, , ,
  79. Intersect(e_2, k_1) → F_3, , ,