比例关系的图形探索：几何“定比分点”与线性刻画

GeoGebra 命令及参数

1. Dilate(B, If[0 < a ≤ 1, 1 - a, 0], A) → B'
2. Vector(B, B') → u
3. Dilate(A, If[2 < a ≤ 3, 3 - a, 0], (0, s)) → A'
4. Vector(A, A') → v
5. Dilate(A', If[3 < a ≤ 4, 4 - a, 0], D) → C'
6. Dilate(D, If[5 < a ≤ 6, 6 - a, 0], (x(D), y(D) + s)) → D'
7. Vector(D, D') → c
8. Dilate(D', If[6 < a ≤ 7, 7 - a, 0], E) → E'
9. Dilate(A, If[8 < a ≤ 9, 9 - a, 0], D) → A'_{1}
10. Segment(A, A'_{1}) → g
11. Dilate(D, If[9 < a ≤ 10, 10 - a, 0], E) → D'_{1}
12. Segment(D, D'_{1}) → h
13. Random(-10, 10) → b_1
14. Random(-10, 10) → n_1
15. Random(1, 10) → d_1
16. If(s ≥ 0, "earn", "lose") → text7
17. If(d > 1, "minutes", "minute") → text8
18. Textfield(p) → InputBox3
19. Textfield(o) → InputBox1
20. If(o ≟ n_1 / d_1, "Yes!", "no") → text9
21. If(p ≟ q, "Yes!", "no") → text10
22. Vector(A', C') → w
23. Vector(D', E') → e