平行四边形的性质 by karabarmaths

GeoGebra 命令及参数

1. Rotate(B_1, α, A) → E
2. Rotate(B_1, α, D) → D_1
3. Ray(D, D_1) → b
4. Segment(A, B_1) → a
5. Line(B, a) → f
6. Intersect(b, f) → C
7. Angle(A, C, D) → λ
8. Angle(B_1, D, D_1) → β
9. Angle(B_1, A, E) → γ
10. Ray(A, E) → c
11. Polygon(A, B, C, D) → P, a_1, g, f_1, c_1
12. Segment(B, D) → h
13. Segment(A, C) → i
14. Intersect(h, i) → O
15. Segment(B, O) → j
16. Segment(O, D) → k
17. Segment(A, O) → l
18. Segment(O, C) → m
19. Angle(C, O, B) → δ
20. Angle(B, C, A) → ε
21. Angle(D, A, C) → ζ
22. Angle(A, B, C) → η
23. Angle(C, D, A) → θ
24. Angle(B, C, D) → ι
25. Angle(D, A, B) → κ
26. Angle(C, B, D) → μ
27. Angle(A, B, D) → ν