余弦定理演示 by John Golden

GeoGebra 命令及参数

1. Polygon(A, B, C) → poly1, c, a, b
2. Line(B, A) → d
3. Line(C, A) → e
4. OrthogonalLine(C, d) → f
5. OrthogonalLine(B, e) → g
6. OrthogonalLine(A, a) → h
7. Intersect(h, a) → D
8. Intersect(d, f) → E
9. Intersect(e, g) → F
10. Polygon(C, B, 4) → poly2, i, j, k, l, G, H
11. Polygon(A, C, 4) → poly3, m, n, p, q, I, J
12. Polygon(B, A, 4) → poly4, r, s, t, a_1, K, L
13. Line(L, K) → b_1
14. Line(I, J) → c_1
15. Intersect(f, b_1) → M
16. Intersect(g, c_1) → N
17. Polygon(A, E, M, K) → poly5, a_2, e_1, m_1, k_1
18. Polygon(A, F, N, J) → poly6, a_3, f_1, n_1, j_1
19. Intersect(h, k) → O
20. Polygon(D, C, H, O) → poly7, d_1, c_2, h_1, o
21. Polygon(D, O, G, B) → poly8, d_2, o_1, g_1, b_2
22. Polygon(B, E, M, L) → poly9, b_3, e_2, m_2, l_1
23. Polygon(C, I, N, F) → poly10, c_3, i_1, n_2, f_2
24. Segment(A, D) → p_1
25. Segment(C, E) → q_1
26. Segment(B, F) → r_1
27. Angle(B, A, C) → α
28. Segment(A, E) → s_1
29. Segment(A, F) → t_1
30. Ray(B, C) → g_2
31. Ray(C, B) → h_2
32. Rotate(C, (-((180° - setalpha) / 2)), C) → C'
33. Rotate(B, (-((180° - (2 * setalpha)) / 2)), C) → B'
34. Ray(C', B') → i_2
35. Rotate(B, (180° - (2 * setalpha)) / 2, B) → B'_1
36. Rotate(C, (180° - (2 * setalpha)) / 2, B) → C'_1
37. Ray(B'_1, C'_1) → j_2
38. Intersect(i_2, j_2) → P
39. Circle(P, C) → k_2
40. Ray(D, A) → l_2
41. Intersect(k_2, l_2) → Q,
42. Textfield(setalpha) → inputBox1
43. Midpoint(B, C) → R
44. Circle(R, C) → p_2
45. Intersect(p_2, l_2) → S,