菱形中的平行线

GeoGebra 命令及参数

1. Segment(A, B) → f
2. Rotate(A, ((α - 180°) * If[(b > 1) ∧ (b ≤ 2), b - 1, 1]), B) → C
3. Rotate(B, ((-α) * If[(b > 2) ∧ (b ≤ 3), b - 2, 1]), C) → D
4. Segment(B, C) → g
5. Segment(C, D) → h
6. Midpoint(D, B) → O
7. OrthogonalLine(O, f) → j
8. Intersect(j, f) → T
9. Circle(O, T) → c
10. Point(g) → Q
11. Tangent(Q, c) → k, l
12. Intersect(k, h) → P
13. Segment(A, P) → m
14. Segment(T, Q) → n
15. Intersect(c, k, 1) → G
16. Intersect(c, g, 1) → H
17. Intersect(c, h, 1) → S
18. Distance(O, P) → EQ
19. Distance(C, P) → CQ
20. Segment(P, Q) → p
21. Segment(A, B_1) → q
22. Rotate(C, ((α - 180°) * If[(b > 3) ∧ (b ≤ 4), b - 3, 1]), D) → A'
23. Segment(D, A') → i
24. Intersect(c, i) → F, E
25. Segment(Q, P') → r
26. Segment(T, Q') → t
27. Segment(A, P'') → s
28. Line(T, r) → d
29. Intersect(d, s) → I
30. Vector(I', T') → u
31. Vector(T', I') → v