Four Points in Normal Form

Four Points in Normal Form
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2023-04-20 04:37
In collections complex-numbers
This example demonstrates how to verify the relationship of four points in normal form using geometric construction and complex number operations. Key mathematical concepts include complex numbers, geometric symmetry, and transformations. Construction involves GeoGebra commands such as LineBisector, Circle, and Tangent. Suitable for high school students or college undergraduates to learn basic geometry and complex number fundamentals.

GeoGebra Commands & Parameters

  1. LineBisector(z_{1}, z_{2}) → l_1
  2. LineBisector(z_{3}, z_{2}) → a_3
  3. Circle(z_{3}, z_{2}, z_{1}) → t_3
  4. Tangent(z_{3}, t_3) → f_4,
  5. Circle(z_{2}, z_{3}, z_{1}) → c_{123}
  6. Tangent(z_{1}, c_{123}) → m_1,
  7. Circle(z_{3}, z_{2}, z_{4}) → c_4
  8. Tangent(z_{3}, c_4) → b_3,
  9. AngularBisector(b_3, f_4) → g_4, h_4
  10. Intersect(a_3, g_4) → H_1
  11. Circle(H_1, z_{2}) → e_4
  12. LineBisector(z_{4}, z_{1}) → l_3
  13. LineBisector(z_{3}, z_{4}) → a_1
  14. Circle(z_{3}, z_{4}, z_{1}) → c_{341}
  15. Tangent(z_{3}, c_{341}) → f_2,
  16. Circle(z_{3}, z_{4}, z_{2}) → c_{342}
  17. Tangent(z_{3}, c_{342}) → b_1,
  18. AngularBisector(b_1, f_2) → g_2, p_2
  19. Intersect(a_1, p_2) → O
  20. Circle(O, z_{3}) → cw_{34}
  21. Circle(z_{1}, z_{3}, z_{4}) → c_{1}
  22. Tangent(z_{1}, c_{1}) → n_3,
  23. Circle(z_{1}, z_{4}, z_{2}) → c_{3}
  24. Tangent(z_{1}, c_{3}) → m_3,
  25. AngularBisector(n_3, m_3) → p_3, q_3
  26. Intersect(p_3, l_3) → F_1
  27. Circle(F_1, z_{4}) → s_3
  28. Intersect(s_3, e_4) → z_o, z_{∞}, ,
  29. Circle(z_{1}, z_{2}, z_{4}) → c_{124}
  30. Tangent(z_{1}, c_{124}) → n_1,
  31. AngularBisector(m_1, n_1) → q_1, r_1
  32. Intersect(l_1, r_1) → L
  33. Circle(L, z_{1}) → s_1
  34. Intersect(s_1, cw_{34}) → z_e, z'_e, ,
  35. Line(z_{1}, z_{2}) → gf
  36. Tangent(z_{3}, c_{123}) → g,
  37. Intersect(gf, g) → A
  38. Circle(z_{2}, z_{1}, z_{3}) → c_{132}
  39. Line(z_{3}, z_{4}) → h
  40. Tangent(z_{1}, c_{132}) → gi,
  41. Intersect(h, gi) → B
  42. Circle(B, z_{1}) → k
  43. Tangent(z_{4}, c_{124}) → n,
  44. Intersect(gf, n) → D
  45. Circle(D, z_{4}) → c4o_{12}
  46. Tangent(z_{2}, c_{123}) → b,
  47. Tangent(z_{1}, c_{123}) → d,
  48. Intersect(d, b) → m_o
  49. Circle(m_o, z_{1}) → c_{o123}
  50. If(Intersect[c_{o123}, c_{132}, 1] ≟ z_{1}, Intersect[c_{o123}, c_{132}, 2], Intersect[c_{o123}, c_{132}, 1]) → zo_4
  51. Intersect(h, gf) → E
  52. Circle(A, z_{3}) → c3o_{12}
  53. Circle(z_{3}, z_{1}, z_{4}) → c_{134}
  54. If(Intersect[c_{134}, c3o_{12}, 1] ≟ z_{3}, Intersect[c_{134}, c3o_{12}, 2], Intersect[c_{134}, c3o_{12}, 1]) → zso_4
  55. Intersect(c_{123}, c4o_{12}, 2) → z''_4
  56. Intersect(c_{123}, c4o_{12}, 1) → z'''_4
  57. If(abs(z''_4 - z_{4}) < abs(z'''_4 - z_{4}), z''_4, z'''_4) → zConz_4
  58. Tangent(z_{1}, c_{3}) → l,
  59. LineBisector(z_{3}, z_{1}) → q
  60. AngularBisector(gi, l) → s, c
  61. Intersect(q, c) → H
  62. Intersect(q, s) → I
  63. LineBisector(z_{3}, z_{4}) → f_1
  64. Tangent(z_{4}, c_{134}) → h_1,
  65. Intersect(l_1, q_1) → M
  66. Circle(M, z_{1}) → t_1
  67. Tangent(z_{1}, s_1) → i_2,
  68. Tangent(z_{1}, t_1) → j_2,
  69. LineBisector(z_{1}, z_{2}) → k_2
  70. AngularBisector(j_2, i_2) → l_2, m_2
  71. Intersect(j_2, k_2) → U
  72. Intersect(k_2, m_2) → V
  73. Intersect(k_2, l_2) → W
  74. LineBisector(z_{3}, z_{2}) → h_2
  75. LineBisector(z_{4}, z_{2}) → n_2
  76. Intersect(a_1, g_2) → N
  77. Circle(N, z_{3}) → cw'_{34}
  78. LineBisector(z'_e, z_e) → r_2
  79. Tangent(z_e, cw_{34}) → s_2,
  80. Tangent(z_e, s_1) → t_2,
  81. AngularBisector(s_2, t_2) → a_2, b_2
  82. Intersect(r_2, b_2) → R
  83. Circle(R, z_e) → w'_{12}
  84. Intersect(r_2, a_2) → S
  85. Circle(S, z_e) → w_{12}
  86. LineBisector(z_{1}, z_{3}) → g_1
  87. Tangent(z_{1}, c_{134}) → i_1,
  88. Tangent(z_{1}, c_{132}) → j_1,
  89. AngularBisector(i_1, j_1) → k_1, p_1
  90. Intersect(g_1, p_1) → J
  91. Circle(J, z_{1}) → cw_{13}
  92. Intersect(g_1, k_1) → K
  93. Circle(K, z_{1}) → cw'_{13}
  94. Circle(z_{4}, z_{2}, z_{3}) → c_{243}
  95. Circle(z_{4}, z_{2}, z_{1}) → c_{241}
  96. LineBisector(z_{4}, z_{2}) → q_2
  97. Tangent(z_{4}, c_{241}) → c_2,
  98. Tangent(z_{4}, c_{243}) → d_2,
  99. AngularBisector(d_2, c_2) → e_2, f_3
  100. Intersect(q_2, f_3) → T
  101. Circle(T, z_{2}) → cw_{24}
  102. Intersect(q_2, e_2) → Z
  103. Circle(Z, z_{2}) → cw'_{24}
  104. Intersect(cw_{24}, cw_{13}) → z_i, z'_i, ,
  105. LineBisector(z_i, z'_i) → g_3
  106. Tangent(z'_i, cw_{24}) → h_3,
  107. Tangent(z'_i, cw_{13}) → i_3,
  108. AngularBisector(i_3, h_3) → j_3, k_3
  109. Intersect(g_3, k_3) → C_1
  110. Circle(C_1, z_i) → d_3
  111. Intersect(g_3, j_3) → D_1
  112. Circle(D_1, z_i) → e_3
  113. Intersect(q_3, l_3) → E_1
  114. Circle(E_1, z_{1}) → r_3
  115. Intersect(h_4, a_3) → G_1
  116. Circle(G_1, z_{2}) → d_4
  117. LineBisector(z_o, z_{∞}) → d_1
  118. Tangent(z_o, e_4) → e_1,
  119. Tangent(z_o, s_3) → i_4,
  120. AngularBisector(i_4, e_1) → j_4, k_4
  121. Intersect(d_1, k_4) → K_1
  122. Circle(K_1, z_o) → p_4
  123. Intersect(d_1, j_4) → L_1
  124. Circle(L_1, z_o) → q_4
  125. Circle(o', e) → c_E
  126. Line(o', e) → g_x
  127. Line(o', i) → g_y

AI Drawing Prompt Reference

Draw four points and construct triangles formed by them with their circumcircles. Start with perpendicular bisectors of point pairs, then add tangents and angle bisectors, finding their intersections. Use these intersections as centers to draw circles through given points, then continue with more tangents and angle bisectors to obtain further intersections. Finally, connect some points to form lines, and find intersections of these lines with circles and tangents, revealing the geometric relationships and symmetry among the four points.
The prompt above was compiled from the original drawing commands and is for reference only.