动态平行四边形问题

GeoGebra 命令及参数

1. Rotate(A, (a * π / 180), B) → A'
2. Angle(A, B, A') → α
3. Segment(A, B) → f
4. Ray(B, A') → g
5. Point(g) → C
6. Line(C, f) → h
7. Line(A, g) → i
8. Intersect(i, h) → D
9. Segment(B, C) → j
10. Min(f, j) → b
11. Circle(B, b) → c
12. Intersect(g, j) → E
13. Intersect(c, g) → F,
14. Segment(F, B) → k
15. Point(k) → G
16. Dilate(A, If[0 < d ≤ 1, 1 - d, 0], B) → A'_1
17. Segment(A, A'_1) → l
18. Circle(B, (0.2 * Min[j, f])) → e
19. Intersect(e, f) → H,
20. Rotate(H, If[1 < d ≤ 2, ((d - 1) * α), α], B) → H'
21. CircleSector(B, H, H') → p
22. Polygon(B, A, D, C) → q1, b_1, a_1, d_1, c_1
23. Circle(C, 2) → q
24. Intersect(q, g) → I, J
25. Circle(D, 2) → r
26. Intersect(r, i) → K, L
27. Dilate(B, If[2 < d ≤ 3, 3 - d, 0], C) → B'
28. Segment(B, B') → m
29. Vector(B, B') → u
30. Translate(p, u) → p'
31. Ray(C, J) → n
32. Ray(D, L) → s
33. Dilate(C, If[3 < d ≤ 4, 4 - d, 0], D) → C'
34. Vector(C, C') → v
35. Translate(p', v) → p''
36. Segment(C, C') → t
37. Dilate(A, If[3 < d ≤ 4, 4 - d, 0], D) → A'_2
38. Segment(A, A'_2) → f_1
39. Intersect(r, h) → M, N
40. Ray(D, M) → g_1
41. Segment(C, G) → h_1
42. Circle(A, h_1) → e_1
43. Intersect(e_1, f) → O,
44. Line(C, O) → i_1
45. Line(A, G) → j_1
46. Intersect(i_1, j_1) → P
47. Line(D, P) → k_1
48. Circle(D, (0.2 * Min[j, f])) → p_1
49. Intersect(p_1, t) → Q,
50. Dilate(C, If[6 < d ≤ 7, 7 - d, 0], G) → C'_1
51. Segment(C, C'_1) → l_1
52. Rotate(C, If[7 < d ≤ 8, ((d - 7) * (π - α)), π - α], G) → C'_2
53. Rotate(C'_1, If[7 < d ≤ 8, ((d - 7) * (π - α)), π - α], G) → R
54. Segment(C'_2, R) → m_1
55. Dilate(G, If[8 < d ≤ 9, 9 - d, 0], A) → G'
56. Vector(G, G') → w
57. Translate(C'_2, w) → S
58. Translate(R, w) → R'
59. Segment(S, R') → n_1
60. Dilate(C, If[9 < d ≤ 10, 10 - d, 0], O) → C'_3
61. Segment(C, C'_3) → q_1
62. Dilate(A, If[10 < d ≤ 11, 11 - d, 0], P) → A'_3
63. Segment(A, A'_3) → r_1
64. Dilate(P, If[11 < d ≤ 12, 12 - d, 0], G) → P'
65. Segment(P, P') → s_1
66. Dilate(D, If[12 < d ≤ 13, 13 - d, 0], P) → D'
67. Segment(D, D') → t_1
68. Rotate(Q, If[13 < d ≤ 14, ((d - 13) * α / 2), α / 2], D) → Q'
69. CircleSector(D, Q, Q') → c_2
70. Rotate(c_2, If[15 < d ≤ 16, ((d - 15) * α / 2), α / 2], D) → d_2