相似变换的性质 by Jeff Hamilton

GeoGebra 命令及参数

1. Polygon(A, B, C) → poly1, c, a, b
2. Segment(A, B) → d
3. Segment(B, C) → e
4. Segment(C, A) → f
5. Textfield(k) → InputBox1
6. Dilate(A, k, O) → A'
7. Dilate(B, k, O) → B'
8. Dilate(C, k, O) → C'
9. Polygon(A', B', C') → poly1', c', a', b'
10. Dilate(A, k, O) → A'_1
11. Dilate(B, k, O) → B'_1
12. Segment(A'_1, B'_1) → d'
13. Dilate(B, k, O) → B'_2
14. Dilate(C, k, O) → C'_1
15. Segment(B'_2, C'_1) → e'
16. Dilate(C, k, O) → C'_2
17. Dilate(A, k, O) → A'_2
18. Segment(C'_2, A'_2) → f'
19. Segment(O, A') → g
20. Segment(O, A) → h
21. Segment(O, B) → i
22. Segment(O, B') → j
23. Segment(O, C') → l
24. Segment(O, C) → m
25. Circle(A, 1) → p
26. Circle(B, 1) → s
27. Intersect(p, f, 1) → D
28. Intersect(p, d, 1) → E
29. Intersect(s, d, 1) → F
30. Intersect(s, e, 1) → G
31. CircleSector(A, D, E) → t
32. CircleSector(B, F, G) → c_1
33. Dilate(A, If[0 < n ≤ 1, 1 - n, 0], A') → A'_3
34. Dilate(B, If[1 < n ≤ 2, 2 - n, 0], B') → B'_3
35. Vector(B, B'_3) → u
36. Vector(A, A'_3) → v
37. Translate(t, v) → t'
38. Translate(c_1, u) → d_1
39. Angle(D, A, E) → α
40. CircleSector(A, E, D) → e_1
41. CircleSector(B, G, F) → f_1
42. Translate(e_1, v) → g_1
43. Translate(f_1, u) → h_1
44. Dilate(A, If[0 < o ≤ 1, 1 - o, 0], A') → A'_4
45. Vector(A, A'_4) → w
46. Dilate(B, If[2 < o ≤ 3, 3 - o, 0], B') → B'_4
47. Vector(B, B'_4) → q
48. Translate(e_1, w) → r
49. Rotate(r, If[1 < o ≤ 2, (((o - 1) * 180))°, 180°], A') → r'
50. Translate(f_1, q) → k_1
51. Rotate(k_1, If[3 < o ≤ 4, (((o - 3) * 180))°, 180°], B') → p_1
52. Translate(t, w) → t'_1
53. Rotate(t'_1, If[1 < o ≤ 2, (((o - 1) * 180))°, 180°], A') → q_1
54. Translate(c_1, q) → r_1
55. Rotate(r_1, If[3 < o ≤ 4, (((o - 3) * 180))°, 180°], B') → s_1