内接平行四边形动画

GeoGebra 命令及参数

1. Line(A, B) → f
2. Line(B, C) → g
3. Line(A, g) → h
4. Line(C, f) → i
5. Intersect(h, i) → D
6. Segment(B, A) → j
7. Segment(A, D) → k
8. Segment(D, C) → l
9. Segment(C, B) → m
10. Midpoint(j) → M
11. Midpoint(k) → P
12. Midpoint(l) → O
13. Midpoint(m) → N
14. Segment(A, N) → n
15. Segment(P, C) → p
16. Segment(B, O) → q
17. Segment(M, D) → r
18. Intersect(n, r) → F
19. Intersect(p, r) → E
20. Intersect(p, q) → H
21. Intersect(n, q) → G
22. Polygon(A, M, F) → t1, f_1, a, m_1
23. Rotate(A, α, M) → A'
24. Rotate(M, α, M) → M'
25. Rotate(F, α, M) → F'
26. Polygon(A', M', F') → t1', f', a', m'
27. Polygon(P, E, D) → t2, d, p_1, e
28. Rotate(P, α, P) → P'
29. Rotate(E, α, P) → E'
30. Rotate(D, α, P) → D'
31. Polygon(P', E', D') → t2', d', p', e'
32. Polygon(H, O, C) → t3, c, h_1, o
33. Polygon(G, N, B) → t4, b, g_1, n_1
34. Rotate(H, α, O) → H'
35. Rotate(O, α, O) → O'
36. Rotate(C, α, O) → C'
37. Polygon(H', O', C') → t3', c', h', o'
38. Rotate(G, α, N) → G'
39. Rotate(N, α, N) → N'
40. Rotate(B, α, N) → B'
41. Polygon(G', N', B') → t4', b', g', n'
42. Polygon(A, F, E, P) → q1, a_1, f_2, e_1, p_2
43. Polygon(D, E, H, O) → q2, d_1, e_2, h_2, o_1
44. Polygon(H, C, N, G) → q3, h_3, c_1, n_2, g_2
45. Polygon(F, M, B, G) → q4, f_3, m_2, b_1, g_3