正方形+菱形=恒定惊喜！（GoGeometry 行动71）

GeoGebra 命令及参数

1. Rotate(B, (a * π / 180), A) → B'
2. Ray(A, B') → j
3. Circle(A, B) → c
4. Intersect(c, j) → E,
5. Line(B, E) → m
6. Segment(A, B) → f
7. Circle(B, f) → h
8. Circle(E, f) → d
9. Intersect(d, h, 1) → C
10. Line(A, C) → l
11. Segment(E, C) → i
12. Circle(B, f) → e
13. Angle(B, A, B') → α
14. Segment(A, E) → g
15. Segment(B, C) → k
16. Dilate(A, If[0 < u ≤ 1, 1 - u, 0], B) → A'
17. Segment(A, A') → j_1
18. Rotate(A, If[1 < u ≤ 2, ((u - 1) * α), α], A) → A'_1
19. Rotate(A', If[1 < u ≤ 2, ((u - 1) * α), α], A) → A''
20. Segment(A'_1, A'') → k_1
21. Rotate(A'_1, If[2 < u ≤ 3, ((u - 2) * (π - α)), π - α], A) → Q
22. Rotate(A'_1, If[2 < u ≤ 3, ((u - 2) * (π - α)), π - α], E) → R
23. Rotate(A'', If[2 < u ≤ 3, ((u - 2) * (π - α)), π - α], E) → A'''_1
24. Segment(R, A'''_1) → m_1
25. Rotate(R, If[3 < u ≤ 4, ((u - 3) * α), α], C) → R'
26. Rotate(A'''_1, If[3 < u ≤ 4, ((u - 3) * α), α], C) → S
27. Segment(R', S) → l_1
28. Polygon(A, B, C, E) → poly1, r_1, s_1, t_1, a_1
29. Circle(A, (0.15 * f)) → d_1
30. Segment(A, A'') → q_1
31. Intersect(d_1, q_1) → T,
32. Intersect(d_1, f) → U,
33. CircleSector(A, U, T) → e_1
34. Segment(A, A'') → r_2
35. Segment(A'', A) → b_2
36. Segment(A, B) → f_3
37. Segment(R, B) → h_3
38. OrthogonalLine(B, b_2) → j_3
39. Intersect(b_2, j_3) → A_1
40. Line(A, R) → r
41. Line(B, A'') → t
42. OrthogonalLine(R, m_1) → k_3
43. Segment(A, B) → m_3
44. Circle(R, m_3) → c_3
45. Circle(B, m_3) → d_3
46. OrthogonalLine(B, l_1) → n_3
47. Intersect(d_3, n_3, 2) → D_1
48. OrthogonalLine(D_1, n_3) → p_3
49. OrthogonalLine(R, l_1) → q_3
50. Intersect(p_3, q_3) → E_1
51. Segment(B, D_1) → r_3
52. Angle(E_1, D_1, B) → ε
53. Dilate(B, If[4 < u ≤ 5, 5 - u, 0], D_1) → B'_1
54. Segment(B, B'_1) → s_3
55. Rotate(B, If[5 < u ≤ 6, ((-(u - 5)) * π / 2), ((-π)) / 2], D_1) → B'_2
56. Rotate(B'_1, If[5 < u ≤ 6, ((-(u - 5)) * π / 2), ((-π)) / 2], D_1) → F_1
57. Segment(B'_2, F_1) → t_3
58. Rotate(B'_2, If[6 < u ≤ 7, ((-(u - 6)) * π / 2), ((-π)) / 2], E_1) → G_1
59. Rotate(E_1, If[6 < u ≤ 7, ((-(u - 6)) * π / 2), ((-π)) / 2], E_1) → H_1
60. Rotate(B'_2, If[6 < u ≤ 7, ((-(u - 6)) * π / 2), ((-π)) / 2], E_1) → I_1
61. Rotate(F_1, If[6 < u ≤ 7, ((-(u - 6)) * π / 2), ((-π)) / 2], E_1) → J_1
62. Segment(I_1, J_1) → a_3
63. Angle(R, E_1, D_1) → ζ
64. Polygon(B, D_1, E_1, R) → poly2, b_3, d_4, e_3, r_4
65. Line(D_1, A) → p
66. Line(A'', B) → f_1
67. Intersect(p, f_1) → F
68. Segment(F, D_1) → h_1
69. Segment(F, A) → i_1
70. Segment(F, B) → n_1
71. Min({h_1, i_1, n_1}) → o
72. Circle(R, (0.4 * o)) → c_1
73. Line(R, B) → b_1
74. Line(R, E_1) → f_2
75. Intersect(c_1, b_1) → H, I
76. Intersect(c_1, f_2) → J, K
77. Rotate(B, 45°, R) → B'_3
78. Angle(B, R, B'_3) → γ
79. Ray(R, B'_3) → g_2
80. Intersect(c_1, g_2) → L, D
81. Dilate(A'', If[7 < u ≤ 8, 8 - u, 0], B) → A'''
82. Segment(A'', A''') → g_1
83. Dilate(B, If[8 < u ≤ 9, 9 - u, 0], F) → B'_4
84. Segment(B, B'_4) → h_2
85. Dilate(D_1, If[8 < u ≤ 9, 9 - u, 0], F) → G
86. Segment(D_1, G) → i_2
87. Dilate(F, If[9 < u ≤ 10, 10 - u, 0], A) → F'
88. Segment(F, F') → j_2
89. Dilate(R, If[9 < u ≤ 10, 10 - u, 0], A) → R'_1
90. Dilate(R, If[10 < u ≤ 11, 11 - u, 0], D_1) → R'_2
91. Segment(R, R'_2) → k_2
92. Rotate(K, If[11 < u ≤ 12, ((-(u - 11)) * π / 4), ((-π)) / 4], R) → K'
93. CircleSector(R, K', K) → c_2
94. Rotate(c_2, If[13 < u ≤ 14, ((-(u - 13)) * π / 4), ((-π)) / 4], R) → d_2
95. Dilate(R, If[14.5 < u ≤ 15.5, 15.5 - u, 0], F) → R'_3
96. Vector(R, R'_3) → v
97. Translate(d_2, v) → e_2
98. Line(F, k_2) → l_2
99. Point(l_2) → M
100. Angle(A, F, M) → β
101. Rotate(e_2, If[15.5 < u ≤ 16.5, ((-(u - 15.5)) * β), (-β)], F) → p_2