内接平行四边形构造

GeoGebra 命令及参数

1. Segment(B, A) → f
2. Line(C_1, f) → g
3. Line(B, D_1) → h
4. Intersect(h, g) → C
5. Line(A, h) → i
6. Intersect(g, i) → D
7. Segment(A, D) → j
8. Segment(B, C) → k
9. Segment(C, D) → l
10. Dilate(A, 1 / 2, B) → A'
11. Dilate(B, 1 / 2, C) → B'
12. Dilate(C, 1 / 2, D) → C'
13. Dilate(D, 1 / 2, A) → D'
14. Segment(A, B') → m
15. Segment(B, C') → n
16. Segment(D, A') → p
17. Segment(C, D') → q
18. Intersect(m, p) → F
19. Intersect(m, n) → G
20. Intersect(n, q) → H
21. Intersect(p, q) → E
22. Polygon(B, A, D, C) → q1, b, a, d, c
23. Polygon(F, G, H, E) → q2, f_1, e, g_1, h_1
24. Intersect(f, p) → I
25. Polygon(I, F, A) → t1, a_1, i_1, f_2
26. Rotate(I, 180°, I) → I'
27. Rotate(F, 180°, I) → F'
28. Rotate(A, 180°, I) → A'_1
29. Polygon(I', F', A'_1) → t1', a'_1, i', f'
30. Polygon(F', B, G, F) → q3, r, b_1, e_1, f_3
31. Intersect(k, m) → J
32. Polygon(G, B, J) → t2, j_1, e_2, b_2
33. Rotate(G, 180°, J) → E'
34. Rotate(B, 180°, J) → B'_1
35. Rotate(J, 180°, J) → J'
36. Polygon(E', B'_1, J') → t2', j', e', b'_1
37. Polygon(G, E', C, H) → q4, e_3, s, c_1, g_2
38. Intersect(l, n) → K
39. Polygon(K, H, C) → t3, c_2, k_1, g_3
40. Rotate(K, 180°, K) → K'
41. Rotate(H, 180°, K) → G'
42. Rotate(C, 180°, K) → C'_1
43. Polygon(K', G', C'_1) → t3', c'_1, k', g'
44. Polygon(E, H, G', D) → q5, h_2, g_4, t, d_1
45. Intersect(j, q) → L
46. Polygon(L, E, D) → t4, d_2, l_1, h_3
47. Rotate(L, 180°, L) → L'
48. Rotate(E, 180°, L) → H'
49. Rotate(D, 180°, L) → D'_1
50. Polygon(L', H', D'_1) → t4', d'_1, l', h'
51. Polygon(F, E, H', A) → q6, f_4, h_4, m_1, a_2
52. PointIn(q3) → Pointq3
53. PointIn(q2) → Pointq2
54. PointIn(q6) → Pointq6
55. PointIn(q5) → Pointq5
56. PointIn(q4) → Pointq4