椭圆与直线的交点构造与相切情形演示

GeoGebra 命令及参数

1. Segment(A, O) → f_1
2. OrthogonalLine(O, f_1) → n
3. Point(n) → C
4. Mirror(C, O) → D
5. Segment(O, D) → l_2
6. Point(n) → I
7. Line(J, I) → l
8. Line(O, A) → k_1
9. Segment(C, O) → g
10. Line(A, g) → h
11. Line(C, f_1) → i
12. Circle(A, C_1) → c
13. Circle(C, Radius[c]) → d_2
14. Intersect(c, h) → D_1, E_1
15. Intersect(d_2, i) → F_1, G
16. Segment(D_1, E_1) → j
17. Segment(F_1, G) → k
18. Mirror(F_1, O) → F'_1
19. Mirror(G, O) → G'
20. Segment(F'_1, G') → k'
21. Mirror(D_1, O) → D'_1
22. Mirror(E_1, O) → E'_1
23. Segment(D'_1, E'_1) → j'
24. Mirror(A, O) → B
25. Segment(O, B) → m
26. Line(C, D) → a
27. Line(A, a) → p
28. Circle(O, C) → d
29. Intersect(d, k_1) → B', A'
30. Segment(A, A') → m_1
31. Segment(B', B) → n_1
32. Intersect(p, l) → E
33. Segment(A, E) → e_A
34. Line(A', a) → q
35. Line(E, f_1) → r
36. Intersect(q, r) → E'
37. Intersect(a, r) → H
38. Segment(A', E') → e_A'
39. Segment(E', E) → l_1
40. Segment(E, H) → s
41. Line(E', I) → l'
42. Intersect(d, l') → Q', P'
43. Line(Q', s) → t
44. Line(P', s) → b
45. Intersect(b, l) → P
46. Intersect(t, l) → Q
47. Intersect(a, b) → K
48. Intersect(a, t) → L
49. Segment(P, K) → g_1
50. Segment(Q, Q') → p_1
51. Segment(P, P') → f
52. Segment(Q, L) → h_1
53. Mirror(K, a) → K'
54. Mirror(L, a) → L'
55. Conic(A, D, B, C, P) → c_1