45度三角函数值动态演示

GeoGebra 命令及参数

1. Center(c) → A
2. Rotate(B, π / 4, A) → B'_2
3. Angle(B, A, B'_2) → γ
4. Intersect(g, i) → D
5. Polygon(A, D, B'_2) → poly2, b'_2, a_2, d
6. CircleArc(A, B'_2, B) → p
7. Point(p) → I
8. Segment(A, I) → s
9. Textfield(r) → InputBox1
10. Dilate(A, If[0 < a ≤ 1, 1 - a, 0], I) → A'_2
11. Segment(A, A'_2) → t
12. Rotate(A, If[3.5 < a ≤ 4.5, ((a - 3.5) * π / 3), π / 3], A) → A'_3
13. CircleArc(A, B, B'_2) → q
14. Dilate(A, If[0 < a ≤ 1, 1 - a, 0], B'_2) → A'
15. Segment(A, A') → f
16. Dilate(A, If[1 < a ≤ 2, 2 - a, 0], D) → A'_1
17. Segment(A, A'_1) → h
18. Dilate(D, If[2 < a ≤ 3, 3 - a, 0], B'_2) → D'
19. Segment(D, D') → j
20. Rotate(A, If[3 < a ≤ 4, ((-(a - 3)) * π / 2), ((-π)) / 2], D) → A'_4
21. Rotate(A'_1, If[3 < a ≤ 4, ((-(a - 3)) * π / 2), ((-π)) / 2], D) → C
22. Segment(A'_4, C) → h'
23. Angle(B'_2, D, A) → α