五边形的旋转对称

GeoGebra 命令及参数

1. Line(A, B) → f
2. Circle(A, B) → c
3. OrthogonalLine(A, f) → g
4. Intersect(c, f, 2) → C
5. Segment(A, C) → h
6. Midpoint(h) → D
7. Circle(D, C) → d
8. Intersect(c, g, 1) → E
9. Ray(E, D) → i
10. Intersect(d, i, 2) → F
11. Intersect(d, i, 1) → G
12. Circle(E, G) → e
13. Circle(E, F) → k
14. Intersect(c, g, 2) → H
15. Intersect(c, e, 2) → I
16. Intersect(c, e, 1) → J
17. Polygon(I, J, 5) → poly1, j, l, m, n, p, K, L, M
18. Point(c) → N
19. Segment(N, A) → q
20. Rotate(N, (-(72°)), A) → N'
21. Angle(N', A, N) → α
22. Polygon(N', N, 5) → poly2, r, s, t, a, b, O, P, Q
23. Angle(P, A, H) → β