GoGeometry 动态几何第172题：等腰三角形与风筝形中的重心性质

GeoGebra 命令及参数

1. Point(Ray[A, (1, 0)]) → B
2. Semicircle(A, B) → c
3. Circle(A, B) → d
4. Intersect(d, yAxis, 2) → C
5. Circle(C, Distance[A, B] / 3) → e
6. Intersect(e, yAxis, 1) → D
7. Midpoint(A, D) → E
8. Semicircle(C, E) → f
9. Intersect(c, f) → F, , ,
10. Segment(G, F) → g
11. OrthogonalLine(F, g) → h
12. Segment(D, F) → i
13. Point(h) → H
14. Point(h) → I
15. Angle(H, F, G) → α
16. Angle(I, F, D) → β
17. Dilate(G, If[0 < a ≤ 1, 1 - a, 0], F) → G'
18. Dilate(D, If[0 < a ≤ 1, 1 - a, 0], F) → D'
19. Segment(G, G') → j
20. Segment(D, D') → k
21. Point(l) → J
22. Angle(J, F, D) → γ
23. Dilate(F, If[3 < a ≤ 4, 4 - a, 0], A) → F'
24. Vector(F, F') → u
25. Translate(D, u) → D'_1
26. Translate(D', u) → D''
27. Segment(D'_1, D'') → k'
28. Rotate(D'_1, If[3 < a ≤ 4, ((-(a - 3)) * γ), (-γ)], D'') → K
29. Rotate(D'', If[3 < a ≤ 4, ((-(a - 3)) * γ), (-γ)], D'') → D'''
30. Segment(K, D''') → k''
31. CircleSector(A, B, C) → p
32. Rotate(K, If[4 < a ≤ 5, ((-(a - 4)) * π), (-π)], K) → K'
33. Rotate(D''', If[4 < a ≤ 5, ((-(a - 4)) * π), (-π)], K) → L
34. Segment(K', L) → k'''
35. Ray(A, B) → m
36. Rotate(K', If[5 < a ≤ 6, ((-(a - 5)) * π), (-π)], L) → K''
37. Rotate(L, If[5 < a ≤ 6, ((-(a - 5)) * π), (-π)], L) → L'
38. Segment(K'', L') → n
39. CircleSector(D, E, C) → q
40. Midpoint(A, B) → M
41. CircleSector(M, B, A) → r
42. CircleArc(A, B, C) → s
43. Segment(A, C) → t