弧度制的几何可视化：角与圆弧的度量

GeoGebra 命令及参数

1. If(Animation ≤ 5, 0, If[5 < Animation < 10, (Animation - 5) / 5, 1]) → i
2. Translate(A, Vector[(If[Animation ≤ 5, Animation / 5, 1] * Vector[A, A + (0, 0, R)])]) → A'
3. Line(A', yAxis) → f
4. Translate(B, Vector[(If[Animation ≤ 5, Animation / 5, 1] * Vector[B, A])]) → B'_{1}
5. Rotate(B'_{1}, -1, f) → C
6. Rotate(B, 1, A) → B'
7. Translate(B', Vector[(If[Animation ≤ 5, Animation / 5, 1] * Vector[B', C])]) → B''
8. CircleSector(A', B'_{1}, B'', xOyPlane) → e_{1}
9. Circle(A, R, xOyPlane) → c
10. CircleSector(A, B, B', xOyPlane) → d
11. Translate(d, Vector[(If[Animation ≤ 5, Animation / 5, 1] * Vector[A, A + (0, 0, R)])]) → d'
12. Segment(E, B) → h
13. Line(A'', yAxis) → g
14. Midpoint(E, A) → D
15. Rotate(e_{1}, i, f) → k
16. Translate(k, Vector[(i * Vector[A', E])]) → k'
17. Rotate(e_{1}, i, g) → e2
18. CircumcircleArc(B', F, B) → e
19. Segment(B', A) → j
20. Segment(A, B) → l
21. Midpoint(l) → G
22. Translate(e, Vector[A, A - (0, 0, 0.05)]) → e'
23. Line(A, zAxis) → n
24. Surface(j, (2 * π) - 1, n) → b
25. Translate(B', Vector[A, A - (0, 0, 0.025)]) → B''_{1}
26. Translate(A, Vector[A, A - (0, 0, 0.025)]) → A'_{1}
27. Segment(B''_{1}, A'_{1}) → j'
28. Surface(j', (2 * π) - 1, n) → o
29. Translate(k, Vector[(i * Vector[A', E])]) → k'_{1}
30. Translate(k', Vector[A', A' + (0, 0.05, 0)]) → k''
31. Translate(k', Vector[A', A' + (0, 0.05, 0)]) → k''_{1}
32. Sequence(Translate[k', Vector[(i * Vector[A', A' + (0, 0.05, 0)])]], i, 0, 1, 0.1) → l1
33. Sequence(Translate[e, Vector[(i * Vector[A, A - (0, 0, 0.05)])]], i, 0, 1, 0.2) → l2
34. Midpoint(j) → H
35. Midpoint(H, A) → I
36. Midpoint(l) → J
37. Midpoint(A, J) → K
38. CircleArc(A, K, I) → p
39. Polygon(I, A, K) → t1, k_1, i_1, a_1
40. Midpoint(I, K) → L
41. Sequence(Translate[k'_{1}, Vector[(i * Vector[A, A + (0, 0, -0.05)])]], i, 0.1, 1, 0.1) → l3
42. CircleArc(A, K, I) → q