三角形中线平行线定理动态演示

GeoGebra 命令及参数

1. Ray(A, B) → f
2. Segment(A, B) → g
3. Rotate(B, α, A) → B'
4. Angle(B, A, B') → β
5. Ray(A, B') → h
6. Point(h) → C
7. Segment(C, B) → i
8. Segment(A, C) → j
9. Midpoint(j) → D
10. Midpoint(i) → E
11. Segment(D, E) → k
12. Midpoint(k) → F
13. Min({j / 2, k / 2}) → a
14. Circle(A, (0.35 * a)) → c
15. Intersect(c, j, 1) → G
16. Intersect(c, g, 1) → H
17. CircleSector(A, H, G) → d
18. Line(D, E) → l
19. Circle(D, 2) → e
20. Circle(E, 2) → p
21. Intersect(e, l, 1) → I
22. Intersect(p, l, 2) → J
23. Ray(D, I) → m
24. Ray(E, J) → n
25. Polygon(A, B, C) → poly1, c_1, a_1, b
26. Dilate(A, If[0 < o ≤ 1, 1 - o, 0], B) → A'
27. Segment(A, A') → q
28. Dilate(A, If[1 < o ≤ 2, 2 - o, 0], D) → A'_1
29. Segment(A, A'_1) → r
30. Dilate(D, If[2 < o ≤ 3, 3 - o, 0], C) → D'
31. Segment(D, D') → s
32. Rotate(A, If[3 < o ≤ 4, ((o - 3) * π), π], D) → A'_2
33. Rotate(A'_1, If[3 < o ≤ 4, ((o - 3) * π), π], D) → K
34. Segment(A'_2, K) → r'
35. Dilate(B, If[4 < o ≤ 5, 5 - o, 0], E) → B'_1
36. Segment(B, B'_1) → t
37. Dilate(E, If[5 < o ≤ 6, 6 - o, 0], C) → E'
38. Segment(E, E') → f_1
39. Rotate(B, If[6 < o ≤ 7, ((-(o - 6)) * π), (-π)], E) → B'_2
40. Rotate(B'_1, If[6 < o ≤ 7, ((-(o - 6)) * π), (-π)], E) → L
41. Segment(B'_2, L) → t'
42. Dilate(D, If[7 < o ≤ 8, 8 - o, 0], F) → D'_1
43. Segment(D, D'_1) → g_1
44. Dilate(A, If[8 < o ≤ 9, 9 - o, 0], D) → A'_3
45. Vector(A, A'_3) → u
46. Translate(d, u) → d'
47. Dilate(F, If[9 < o ≤ 10, 10 - o, 0], E) → F'
48. Segment(F, F') → h_1