探索：垂直于平行线的截线所成的特殊角关系

GeoGebra 命令及参数

1. Point(f) → A
2. Circle(A, 2) → c
3. Intersect(c, f, 2) → B
4. Rotate(B, (a * π / 180), A) → B'
5. Rotate(f, (b * π / 180), A) → f'
6. Intersect(c, f', 2) → F
7. Rotate(F, (a * π / 180), A) → F'
8. Angle(F, A, F') → α
9. Line(A, F') → g
10. Intersect(c, g, 1) → C
11. Ray(A, F') → h
12. Ray(A, C) → i
13. Intersect(c, f', 1) → D
14. Ray(A, F) → j
15. Ray(A, C) → k
16. Ray(A, D) → l
17. Point(l) → E
18. Point(h) → G
19. Point(k) → H
20. Point(j) → I
21. Line(G, j) → m
22. Circle(G, 1) → d
23. Intersect(d, m) → J, K
24. Intersect(d, h) → L, M
25. Ray(G, K) → n
26. Ray(G, J) → p
27. Point(n) → O
28. Point(p) → P
29. Intersect(d, h, 2) → Q
30. Ray(G, Q) → q
31. Segment(A, G) → r
32. Point(q) → N
33. Circle(G, 1.5) → c_1
34. Circle(A, 1.5) → d_1
35. Intersect(c_1, n, 1) → R
36. Intersect(c_1, q, 1) → S
37. Intersect(c_1, p, 1) → T
38. Intersect(c_1, r, 1) → U
39. Intersect(d_1, j, 1) → V
40. Intersect(d_1, r, 1) → W
41. Intersect(d_1, l) → Z,
42. Intersect(d_1, k, 1) → A_1
43. CircleSector(G, R, S) → e_1
44. CircleSector(G, S, T) → f_1
45. CircleSector(G, T, U) → g_1
46. CircleSector(G, U, R) → h_1
47. CircleSector(A, V, W) → k_1
48. CircleSector(A, W, Z) → p_1
49. CircleSector(A, Z, A_1) → q_1
50. CircleSector(A, A_1, V) → r_1