整数乘法可视化 by mathspace

GeoGebra 命令及参数

1. OrthogonalLine(C, yAxis) → b
2. Intersect(b, yAxis) → D
3. OrthogonalLine(C, xAxis) → a
4. Intersect(a, xAxis) → B
5. Intersect(xAxis, yAxis) → A
6. Polygon(A, B, C, D) → poligon1, a_1, b_1, c, d
7. Midpoint(A, C) → E
8. CircleArc(E, A, D) → e
9. CircleArc(E, D, A) → f
10. Polygon(A, B, C, D) → poly1, a_2, b_2, c_1, d_1
11. Midpoint(a_2) → xplus
12. Midpoint(b_2) → yminus
13. Midpoint(c_1) → xminus
14. Midpoint(d_1) → yplus
15. If(x(C) ≥ 0 ∧ h ≥ 0, xminus, If[x(C) < 0 ∧ h ≥ 0, xplus, If[x(C) ≥ 0 ∧ h < 0, xplus, If[x(C) < 0 ∧ h < 0, xminus]]]) → G
16. If(x(C) ≥ 0 ∧ h ≥ 0, yminus, If[x(C) < 0 ∧ h ≥ 0, yplus, If[x(C) ≥ 0 ∧ h < 0, yminus, If[x(C) < 0 ∧ h < 0, yplus]]]) → H
17. Corner(text4, 1) → textc1
18. Corner(text4, 2) → textc2
19. Midpoint(textc1, textc2) → c12
20. Corner(text4, 4) → textc4
21. Midpoint(textc1, textc4) → c13
22. Corner(text4, 3) → textc3