旋转平行四边形：几何变换与作图

GeoGebra 命令及参数

1. Midpoint(A, C) → E
2. Rotate(A, (-α), E) → A'
3. Rotate(B, (-α), E) → B'
4. Rotate(C, (-α), E) → C'
5. Rotate(D, (-α), E) → D'
6. Segment(A, B) → f
7. Segment(A', B') → g
8. Segment(B, C) → h
9. Segment(B', C') → i
10. Segment(C, D) → j
11. Segment(C', D') → k
12. Segment(D, A) → l
13. Segment(D', A') → m
14. Segment(B, D) → n
15. Segment(B', D') → p
16. Segment(A, C) → q
17. Segment(A', C') → r
18. Segment(A, E) → s
19. Segment(A', E) → t
20. Segment(B, E) → a
21. Segment(B', E) → b
22. Segment(C, E) → c
23. Segment(C', E) → d
24. Segment(D, E) → e
25. Segment(D', E) → f_1
26. Angle(E, A, B) → β
27. Angle(E, A', B') → γ
28. Angle(E, B, C) → δ
29. Angle(E, B', C') → ε
30. Angle(B, C, E) → ζ
31. Angle(B', C', E) → η
32. Angle(B, E, A) → θ
33. Angle(B', E, A') → ι