绿红圆交点与几何构造

GeoGebra 命令及参数

1. Intersect(xAxis, yAxis) → A
2. Polygon(A, B, 4) → poly1, a, b, c, d_1, C, D
3. PointIn(poly1) → E
4. Mirror(E, a) → E'
5. Mirror(E, d_1) → E'_1
6. Mirror(E'_1, a) → F
7. Polygon(F, E', E, E'_1) → poly2, f, d, e, e'_1
8. Midpoint(E'_1, F) → G
9. Midpoint(E, E') → H
10. Midpoint(G, H) → I
11. Midpoint(I, H) → J
12. Midpoint(G, I) → K
13. Circle(K, I) → g
14. Circle(J, H) → h
15. Midpoint(E'_1, E) → L
16. Segment(I, L) → i
17. Circle(L, r) → k
18. Intersect(k, i, 1) → M
19. Circle(M, L) → s
20. Mirror(s, I) → s'