平行四边形性质探索 by Ben Graber

GeoGebra 命令及参数

1. Segment(A, B) → a
2. Rotate(B, α, A) → B'
3. Angle(B, A, B') → β
4. Rotate(A, (-(180° - α)), B) → A'
5. Angle(A', B, A) → γ
6. Segment(A, B') → b
7. Point(b) → C
8. Line(C, a) → c
9. Line(B, b) → d
10. Intersect(c, d) → D
11. Segment(A, C) → e
12. Segment(C, D) → f
13. Segment(D, B) → g
14. Segment(C, B) → h
15. Segment(A, D) → i
16. Intersect(h, i) → E
17. Angle(A, C, D) → δ
18. Angle(C, D, B) → ε
19. Segment(E, C) → j
20. Segment(E, D) → k
21. Segment(E, B) → l
22. Segment(E, A) → m
23. Angle(C, E, A) → ζ
24. Angle(D, E, C) → η
25. Angle(B, E, D) → θ
26. Angle(A, E, B) → ι
27. Point(Circle[F, 5]) → G
28. Segment(F, G) → n
29. Rotate(G, α, F) → G'
30. Angle(G, F, G') → κ
31. Line(G', n) → p
32. Segment(F, G') → q
33. Line(G, q) → r
34. Intersect(p, r) → H
35. Intersect(p, q) → I
36. Segment(I, H) → s
37. Segment(G, H) → t
38. Segment(G, I) → a_1
39. Segment(F, H) → b_1
40. Angle(F, I, H) → λ
41. Angle(H, G, F) → μ
42. Angle(I, H, G) → ν
43. Intersect(a_1, b_1) → J
44. Segment(J, I) → c_1
45. Segment(J, G) → d_1
46. Segment(F, J) → e_1
47. Segment(J, H) → f_1
48. Angle(H, J, I) → ξ
49. Angle(I, J, F) → ο
50. Angle(G, J, H) → ρ
51. Angle(F, J, G) → σ