保持与线段固定距离的轨迹

GeoGebra 命令及参数

1. Segment(A, B) → a
2. OrthogonalLine(P, a) → b
3. Intersect(b, a) → D
4. Segment(P, D) → c
5. Segment(P, B) → d
6. Segment(P, A) → e
7. If(x(P) < x(A), e) → f
8. If(x(P) > x(B), d) → g
9. Line(A, B) → h
10. Point(h) → H
11. If(y(P) > -2, Angle[H, D, P], Angle[P, D, H]) → α
12. If(x(P) < x(A), If[abs(f - 5) ≤ 0.02, P]) → F
13. If(x(P) > x(B), If[abs(g - 5) ≤ 0.02, P]) → E
14. If(abs(c - 5) ≤ 0.02, P) → G