三角形的内心、外心、重心和垂心

GeoGebra 命令及参数

1. Polygon(A, B, C) → poly1, c, a, b
2. AngularBisector(c, a) → d, e
3. AngularBisector(c, b) → f, g
4. AngularBisector(a, b) → h, i
5. Intersect(e, g) → D
6. OrthogonalLine(D, a) → k
7. Intersect(k, a) → E
8. Circle(D, E) → p
9. Segment(D, E) → l
10. Segment(E, C) → m
11. Angle(C, E, D) → α
12. LineBisector(a) → q
13. LineBisector(c) → r
14. LineBisector(b) → s
15. Intersect(q, r) → F
16. Intersect(r, c) → G
17. Intersect(s, b) → H
18. Intersect(q, a) → I
19. Segment(B, G) → t
20. Segment(G, A) → a_1
21. Angle(c, r) → β
22. Circle(F, B) → c_1
23. Segment(A, H) → b_1
24. Segment(H, C) → d_1
25. Segment(B, I) → e_1
26. Segment(I, C) → f_1
27. Angle(f_1, q) → γ
28. Angle(s, b_1) → δ
29. OrthogonalLine(A, a) → g_1
30. OrthogonalLine(B, b) → h_1
31. OrthogonalLine(C, c) → i_1
32. Intersect(g_1, h_1) → J
33. Line(B, C) → j_1
34. Line(B, A) → k_1
35. Line(A, C) → l_1
36. Intersect(g_1, j_1) → K
37. Intersect(h_1, l_1) → L
38. Intersect(i_1, k_1) → M
39. Angle(i_1, k_1) → ε
40. Angle(j_1, g_1) → ζ
41. Midpoint(A, K) → N
42. Midpoint(B, L) → O
43. Midpoint(C, M) → P
44. Angle(h_1, l_1) → η
45. Midpoint(t) → Q
46. Midpoint(c) → R
47. Midpoint(b) → S
48. Midpoint(a) → T
49. Segment(A, T) → m_1
50. Segment(B, S) → n_1
51. Segment(C, R) → p_1
52. Intersect(m_1, n_1) → U
53. Line(F, J) → q_1