椭圆与同心圆的构造示例

GeoGebra 命令及参数

1. Circle(A, B) → c
2. Circle(A, C) → d
3. Point(c) → D
4. Ray(A, D) → f
5. Intersect(d, f, 1) → E
6. Intersect(g, eq1) → F
7. Segment(E, F) → h
8. Segment(F, D) → i
9. Locus(F, D) → loc1
10. Polygon(E, F, D) → t1, d_1, e, f_1
11. Radius(c) → a
12. Radius(d) → b
13. Angle(E, F, D) → α
14. Circle(A_{1}, B_{1}) → c_{1}
15. Point(c_{1}) → D_{1}
16. Radius(c_{1}) → a_{1}
17. Circle(A_{2}, C_{1}) → d_{2}
18. Radius(d_{2}) → b_{1}