梯形性质探索

GeoGebra 命令及参数

1. Line(A, B) → a
2. Line(C, a) → b
3. Point(b) → D
4. Polygon(C, A, B, D) → poly1, c, a_1, b_1, d
5. Angle(poly1) → α, β, γ, δ
6. Segment(A, D) → AD
7. Segment(C, B) → CB
8. Intersect(AD, CB) → E
9. Segment(E, D) → ED
10. Segment(E, C) → EC
11. Segment(E, A) → EA
12. Segment(E, B) → EB
13. Segment(A, D) → h
14. Segment(C, B) → i
15. Angle(i, h) → ε
16. Segment(A, D) → k
17. Segment(C, B) → l
18. Angle(B, A, D) → ζ
19. Angle(D, A, C) → η
20. Angle(A, C, B) → θ
21. Angle(B, C, D) → ι
22. Angle(C, D, A) → κ
23. Angle(A, D, B) → λ
24. Angle(D, B, C) → μ
25. Angle(C, B, A) → ν
26. Line(C, D) → n
27. Line(A, B) → p
28. Line(D, B) → q
29. Line(C, A) → r
30. Segment(C, D) → CD
31. Segment(D, B) → DB
32. Segment(B, A) → BA
33. Segment(A, C) → AC
34. Polygon(F, G, H, I) → poly2, f_1, g_1, h_1, i_1