四边形面积动态演示与构造

GeoGebra 命令及参数

1. Segment(F_1, G_1) → i_2
2. Line(H_1, i_2) → j_2
3. Point(j_2) → I_1
4. Semicircle(G_1, I_1) → t_2
5. Semicircle(T, U) → c_2
6. Segment(E, F) → e
7. Line(G, e) → g
8. Segment(F, G) → f
9. Line(E, f) → h
10. Intersect(g, h) → H
11. Polygon(E, F, G, H) → poly2, e_1, f_1, g_1, h_1
12. OrthogonalLine(F, h_1) → i
13. Intersect(i, h) → J
14. Polygon(J, F, G, H) → poly4, j_1, f_2, g_2, h_2
15. Intersect(j_1, h_2) → Q
16. OrthogonalLine(G, f) → j
17. Intersect(h, j) → K
18. Segment(J, K) → m
19. Segment(A, B) → a
20. OrthogonalLine(B, a) → b
21. OrthogonalLine(A, a) → c
22. Point(b) → C
23. OrthogonalLine(C, b) → d
24. Intersect(c, d) → D
25. Polygon(A, B, C, D) → poly1, a_1, b_1, c_1, d_1
26. Angle(D, A, B) → α
27. Intersect(h, h_1) → I
28. Segment(E, K) → k
29. Distance(E, J) → distanceEJ
30. Distance(F, J) → distanceFJ
31. Point(m) → L
32. Circle(L, distanceEJ) → p
33. Circle(L, distanceFJ) → q
34. Line(F, G) → l
35. Intersect(q, l) → M, N_1
36. Intersect(p, h) → N, O
37. Polygon(L, M, O) → poly3, o, l_1, m_1
38. Angle(M, L, O) → β
39. Segment(P, H) → n
40. Segment(F, P) → r
41. Polygon(R, T, U) → poly5, u, r_1, t
42. Midpoint(r_1) → V
43. Circle(V, T) → s
44. Point(c_2) → W
45. Ray(W, V) → i_1
46. Intersect(s, i_1) → Z, A_1
47. Segment(A_1, W) → k_1
48. Ray(R, V) → n_1
49. Circle(V, R) → p_1
50. Intersect(p_1, n_1) → B_1, C_1
51. Circle(A_1, u) → s_1
52. Circle(W, t) → t_1
53. Intersect(s_1, t_1, 2) → D_1
54. Polygon(W, D_1, A_1) → poly6, a_2, w, d_2
55. Ray(R, V) → q_1
56. OrthogonalLine(W, t) → b_2
57. Intersect(t, b_2) → E_1
58. Segment(W, E_1) → e_2
59. Segment(G_1, I_1) → k_2
60. Point(j_2) → J_1
61. Segment(F_1, J_1) → l_2
62. Midpoint(k_2) → K_1
63. Circle(K_1, I_1) → p_2
64. Point(t_2) → L_1
65. Ray(L_1, K_1) → m_2
66. Intersect(p_2, m_2) → M_1, O_1
67. Angle(G_1, I_1, H_1) → γ
68. Rotate(K_1, γ, L_1) → P_1
69. Angle(K_1, L_1, P_1) → δ
70. Ray(L_1, P_1) → n_2
71. Angle(F_1, G_1, I_1) → ε
72. Rotate(K_1, -ε, O_1) → Q_1
73. Angle(Q_1, O_1, K_1) → ζ
74. Ray(O_1, Q_1) → q_2
75. Distance(I_1, J_1) → distanceI1J1
76. Distance(G_1, F_1) → distanceG1F1
77. Circle(L_1, distanceI1J1) → r_2
78. Circle(O_1, distanceG1F1) → s_2
79. Intersect(s_2, q_2, 1) → R_1
80. Intersect(r_2, n_2, 1) → S_1
81. Polygon(L_1, O_1, R_1, S_1) → poly7, l_3, o_1, r_3, s_3
82. Polygon(J_1, F_1, G_1, I_1) → poly8, j_3, f_3, g_3, i_3
83. OrthogonalLine(F_1, i_3) → a_3
84. Intersect(j_2, a_3) → T_1
85. Segment(F_1, T_1) → b_3
86. Angle(F_1, T_1, J_1) → η
87. Point(u) → Z_1
88. Point(r_1) → A_2
89. Segment(Z_1, A_2) → d_3
90. Polygon(U_1, V_1, W_1) → poly9, w_1, u_1, v_1
91. Circle(U_1, V_1) → c_3
92. Circle(W_1, V_1) → e_3
93. Intersect(c_3, e_3, 2) → B_2
94. Polygon(U_1, B_2, W_1) → poly10, w_2, u_2, b_4
95. Segment(V_1, B_2) → h_3