三角形内心构造与性质演示

GeoGebra 命令及参数

1. Polygon(A, B, C) → poly1, c, a, b
2. AngularBisector(C, B, A) → f
3. AngularBisector(B, C, A) → g
4. AngularBisector(C, A, B) → h
5. Intersect(g, f) → D
6. Intersect(h, poly1) → E, F
7. Intersect(g, poly1) → G, H
8. Intersect(f, b) → I
9. Angle(F, B, D) → α
10. Angle(D, B, H) → β
11. Angle(D, A, H) → γ
12. Angle(I, A, D) → δ
13. Angle(I, C, D) → ε
14. Angle(D, C, F) → ζ
15. OrthogonalLine(D, c) → i
16. Intersect(i, c) → J
17. Angle(D, J, A) → η
18. Segment(D, J) → j
19. OrthogonalLine(D, a) → k
20. OrthogonalLine(D, b) → l
21. Intersect(b, l) → K
22. Intersect(a, k) → L
23. Segment(D, L) → m
24. Segment(D, K) → n
25. Angle(D, K, A) → θ
26. Angle(D, L, C) → ι
27. Circle(D, K) → d