三角形的面积公式演示

GeoGebra 命令及参数

1. Line(A, xAxis) → a
2. Point(a) → B
3. Polygon(A, B, C) → poly1, c, a_1, b
4. Line(A, yAxis) → d
5. Line(C, xAxis) → e
6. Line(B, yAxis) → f
7. Intersect(e, f) → D
8. Intersect(d, e) → E
9. Polygon(B, D, C) → poly2, c_1, b_1, d_1
10. Polygon(A, C, E) → poly3, e_1, a_2, c_2
11. Vector(A, C) → u
12. Distance(A, C) → AC
13. Vector(A, U) → v_1
14. Translate(A, v_1) → A'
15. Translate(C, v_1) → C'
16. Translate(E, v_1) → E'
17. Polygon(A', C', E') → poly3', e', a', c'
18. Rotate(A', β, A') → A''
19. Rotate(C', β, A') → C''
20. Rotate(E', β, A') → E''
21. Polygon(A'', C'', E'') → poly3'', e'', a'', v
22. Vector(B, C) → w
23. Distance(B, C) → BC
24. Vector(B, V) → v_2
25. Translate(B, v_2) → B'
26. Translate(D, v_2) → D'
27. Translate(C, v_2) → C'_1
28. Polygon(B', D', C'_1) → poly2', c'_1, b', d'
29. Rotate(B', -γ, V) → B''
30. Rotate(D', -γ, V) → D''
31. Rotate(C'_1, -γ, V) → F
32. Polygon(B'', D'', F) → poly2'', f_1, b'', d''