二次曲线（版本2）

GeoGebra 命令及参数

1. Point(zAxis) → A
2. Point(zAxis) → B
3. Segment(A, B) → f
4. Intersect(yAxis, f) → C
5. Cone(A, C, 2) → a, c, b
6. Cone(B, C, 2) → d, e, g
7. Point(yAxis) → D
8. Point(yAxis) → E
9. Line(D, E) → h
10. Intersect(zAxis, q) → F
11. Line(F, h) → i
12. Rotate(q, α, i) → q'
13. IntersectPath(q', a) → k
14. Corner(k) → G, H, I, J
15. IntersectPath(q', d) → r
16. Corner(r) → K, L, M, N