外角定理演示

GeoGebra 命令及参数

1. Point(f) → A
2. Point(f) → B
3. Polygon(A, B, C) → t1, c, a, b
4. Angle(C, B, A) → α
5. Angle(B, A, C) → β
6. Angle(A, C, B) → γ
7. Midpoint(A, C) → D
8. Midpoint(B, C) → E
9. Polygon(E, B, (x(E), y(B))) → t2, g, e, b_1
10. Rotate(t2, d, E) → t2'
11. Polygon(A, D, (x(D), y(A))) → t3, h, a_1, d_1
12. InteriorAngles(t2') → δ, ε, ζ
13. Segment((x(B), y(B)), (x(E), y(E))) → i
14. Rotate(i, d, E) → i'
15. Segment((x(D), y(D)), (x(A), y(A))) → j
16. Ray(A, C) → l
17. Segment(A, C) → k
18. Line(A, C) → n
19. Point(n) → I
20. Slope(n) → o
21. Vector(A, J) → u
22. Translate(t3, u) → t3'
23. InteriorAngles(t3') → η, θ, ι
24. Point(l) → K
25. Angle(B, C, K) → κ