三角形重心、垂心与外心的构造演示

GeoGebra 命令及参数

1. Polygon(A, B, C) → poly1, c, a, b
2. Point(poly1) → D
3. Circle(A, Segment[A, D]) → d
4. Circle(C, Segment[A, D]) → e
5. Intersect(d, e, 2) → E
6. Intersect(d, e, 1) → F
7. Line(E, F) → f
8. Point(poly1) → G
9. Circle(B, Segment[B, G]) → g
10. Circle(A, Segment[B, G]) → h
11. Intersect(g, h, 2) → H
12. Intersect(g, h, 1) → I
13. Line(H, I) → i
14. Point(poly1) → J
15. Circle(B, Segment[B, J]) → k
16. Circle(C, Segment[B, J]) → p
17. Intersect(k, p, 1) → K
18. Intersect(k, p, 2) → L
19. Line(K, L) → j
20. Intersect(f, i) → M
21. Circle(B, N) → q
22. Intersect(q, b, 1) → O
23. Intersect(q, b, 2) → P
24. Circle(O, D) → r
25. Circle(P, Segment[O, D]) → s
26. Intersect(r, s, 1) → Q
27. Intersect(r, s, 2) → R
28. Line(Q, R) → l
29. Circle(C, S) → t
30. Intersect(t, c, 1) → T
31. Circle(B, U) → c_1
32. Circle(T, Segment[B, U]) → d_1
33. Intersect(c_1, d_1, 2) → V
34. Line(V, C) → m
35. Circle(A, W) → e_1
36. Intersect(e_1, a, 2) → Z
37. Intersect(e_1, a, 1) → A_1
38. Point(e_1) → B_1
39. Circle(Z, B_1) → f_1
40. Circle(A_1, Segment[Z, B_1]) → g_1
41. Intersect(f_1, g_1, 2) → C_1
42. Line(C_1, A) → n
43. Intersect(f, b) → D_1
44. Intersect(j, a) → E_1
45. Intersect(i, c) → F_1
46. Line(F_1, C) → a_1
47. Line(D_1, B) → b_1
48. Line(E_1, A) → h_1
49. Intersect(a_1, b_1) → G_1
50. Line(M, G_1) → i_1
51. Intersect(t, c, 2) → H_1
52. Intersect(l, m) → I_1