特伯定理：三角形三边上正方形中心的等边三角形构造

GeoGebra 命令及参数

1. Segment(B, A) → f
2. Segment(B, C) → g
3. Line(C, f) → h
4. Line(A, g) → i
5. Intersect(h, i) → D
6. Polygon(B, C, D, A) → q1, a, c, d, b
7. Polygon(A, D, 4) → poly1, j, k, l, m, E, F
8. Polygon(D, C, 4) → poly2, n, p, q, r, G, H
9. Polygon(C, B, 4) → poly3, s, t, e, f_1, I, J
10. Polygon(B, A, 4) → poly4, g_1, h_1, i_1, j_1, K, L
11. Centroid(poly4) → M
12. Centroid(poly1) → N
13. Centroid(poly2) → O
14. Centroid(poly3) → P
15. Polygon(M, N, O, P) → q2, m_1, n_1, o, p_1
16. Segment(L, B) → k_1
17. Segment(L, K) → l_1
18. Segment(K, A) → q_1
19. Segment(F, A) → r_1
20. Segment(F, E) → s_1
21. Segment(E, D) → t_1
22. Segment(D, H) → a_1
23. Segment(H, G) → b_1
24. Segment(G, C) → c_1
25. Segment(J, C) → d_1
26. Segment(B, I) → e_1
27. Segment(I, J) → f_2
28. Segment(M, P) → g_2
29. Segment(P, O) → h_2
30. Segment(O, N) → i_2
31. Segment(N, M) → j_2