同心圆与割线动态演示

GeoGebra 命令及参数

1. Circle(A, a) → c
2. Circle(A, b) → d
3. Point(c) → D
4. Tangent(D, d) → f, g
5. Intersect(d, g) → E
6. Intersect(d, f) → F
7. Intersect(c, g, 2) → G
8. Intersect(c, f, 2) → H
9. CircleArc(A, H, G) → e
10. Point(e) → I
11. Segment(D, I) → h
12. Intersect(d, h, 1) → J
13. Intersect(d, h, 2) → K
14. Dilate(D, If[0 < i ≤ 1, 1 - i, 0], J) → D'
15. Segment(D, D') → j
16. Dilate(J, If[1 < i ≤ 2, 2 - i, 0], K) → J'
17. Segment(J, J') → k
18. Dilate(K, If[2 < i ≤ 3, 3 - i, 0], I) → K'
19. Segment(K, K') → l
20. Angle(K, A, J) → α
21. Rotate(D, If[3 < i ≤ 4, ((-(i - 3)) * α), (-α)], A) → D'_1
22. Rotate(D', If[3 < i ≤ 4, ((-(i - 3)) * α), (-α)], A) → D''
23. Segment(D'_1, D'') → j'
24. Rotate(D, (-α), J) → D'_2
25. Rotate(D', (-α), J) → D''_1
26. Segment(D'_2, D''_1) → j'_1
27. Angle(K, J, D'_2) → β
28. Rotate(D'_1, If[4 < i ≤ 5, ((-(i - 4)) * β), (-β)], K) → L
29. Rotate(D'', If[4 < i ≤ 5, ((-(i - 4)) * β), (-β)], K) → D'''
30. Segment(L, D''') → j''