圆内接四边形探究：圆周角定理的直接推论

GeoGebra 命令及参数

1. Circle(A, B) → c
2. Point(c) → C
3. Rotate(C, 2°, A) → C'
4. CircleArc(A, C', C) → d
5. Point(d) → D
6. CircleArc(A, D, C) → e
7. Point(e) → E
8. CircleArc(A, E, C) → f
9. Point(f) → F
10. CircleArc(A, F, C) → g
11. Point(g) → G
12. Segment(D, E) → b
13. Segment(E, F) → h
14. Segment(D, G) → a
15. Segment(G, F) → i
16. Circle(F, (0.2 * Distance[A, B])) → k
17. Circle(E, (0.2 * Distance[A, B])) → p
18. Circle(G, (0.2 * Distance[A, B])) → q
19. Circle(D, (0.2 * Distance[A, B])) → r
20. Intersect(k, i, 1) → H
21. Intersect(k, h, 1) → I
22. Intersect(p, h, 1) → J
23. Intersect(p, b, 1) → K
24. Intersect(r, a, 1) → L
25. Intersect(r, b, 1) → M
26. Intersect(q, a, 1) → N
27. Intersect(q, i, 1) → O
28. CircleSector(G, N, O) → s
29. CircleSector(F, H, I) → t
30. CircleSector(E, J, K) → c_1
31. CircleSector(D, M, L) → d_1
32. Circle(A, B) → e_1
33. Dilate(E, If[0 < j ≤ 1, 1 - j, 0], G) → E'
34. Vector(E, E') → u
35. Translate(c_1, u) → f_1
36. CircleArc(E, J, K) → g_1
37. Translate(J, u) → J'
38. Angle(O, G, J') → α
39. Rotate(f_1, If[1 < j ≤ 2, ((-(j - 1)) * α), (-α)], G) → h_1
40. Ray(D, G) → l
41. Point(l) → P
42. Ray(G, P) → m
43. Dilate(F, If[2 < j ≤ 3, 3 - j, 0], D) → F'
44. Vector(F, F') → v
45. Ray(G, D) → n
46. Point(n) → Q
47. Ray(D, Q) → a_1
48. Translate(t, v) → t'
49. CircleArc(F, H, I) → k_1
50. Translate(I, v) → I'
51. Angle(I', D, M) → β
52. Rotate(t', If[3 < j ≤ 4, ((j - 3) * β), β], D) → t''
53. Polygon(G, D, E, F) → poly1, g_2, d_2, e_2, f_2