抛物线构造仪器：基于几何作图的动态演示

GeoGebra 命令及参数

1. Segment((0, 0), (3, 0)) → a
2. Point(a) → F
3. Segment(((-1 * x(F)), (-1 * sqrt(36 - (4 * x(F)^(2))))), ((-1 * x(F)), sqrt(36 - (4 * x(F)^(2))))) → j
4. Point(j) → S
5. Polygon(K_S, C_S, D_S, E_S, F_S, G_S, J_S, I_S) → poly1, h, i, s, t, a_1, b_1, c_1, d_1
6. Circle(F, 3) → k
7. Segment(S, F) → c
8. LineBisector(c) → d
9. Intersect(k, d) → B, C
10. OrthogonalLine(S, yAxis) → b
11. Intersect(d, c) → A
12. Parabola(F, l) → p
13. UnitVector(Vector[B, F]) → u_1
14. UnitOrthogonalVector(Vector[B, F]) → u_2
15. Polygon(L_1, L_2, L_3, L_4) → Vieleck1, m, n, q, r
16. Polygon(N_1, N_2, N_3, N_4) → Vieleck2, n_1, n_2, n_3, n_4
17. UnitVector(Vector[F, C]) → v_1
18. UnitOrthogonalVector(Vector[F, C]) → v_2
19. Polygon(M_1, M_2, M_3, M_4) → Vieleck3, m_1, m_2, m_3, m_4
20. Polygon(O_1, O_2, O_3, O_4) → Vieleck4, o_1, o_2, o_3, o_4
21. Line(S, xAxis) → e_1
22. Intersect(d, e_1) → P
23. Polygon((x(S), y(S) - 0.05), (x(S) + 9, y(S) - 0.05), (x(S) + 9, y(S) + 0.05), (x(S), y(S) + 0.05)) → Vieleck5, f_1, g_1, h_1, i_1
24. Point(d) → D
25. Point(d) → E
26. UnitOrthogonalVector(Vector[B, P]) → u
27. Polygon(A_d, B_d, F_d, E_d) → Vieleck6, a_d, b_d, f_d, e_d
28. Polygon(C_d, D_d, H_d, G_d) → Vieleck7, j_1, k_1, l_1, p_1