直线与曲线的斜率、平均率与瞬时率

GeoGebra 命令及参数

1. Point(c) → P
2. Tangent(P, c) → a,
3. Point(c) → Q
4. Line(P, Q) → b
5. Point(c) → A
6. Line(P, A) → d
7. Point(c) → B
8. Line(P, B) → e
9. Point(c) → C
10. Tangent(C, c) → f,
11. Vector(P, (x(Q), y(P))) → u
12. Vector((x(Q), y(P)), Q) → v
13. Line(P, Q) → j
14. Point(j) → Q'
15. Vector((x(Q'), y(P)), Q') → w
16. Vector(P, (x(Q'), y(P))) → z
17. Point(j) → C'
18. Segment(C', D') → l
19. OrthogonalLine(D', l) → m
20. Intersect(m, j) → E
21. Polygon(C', D', E) → poly1, e_1, c', d_1
22. Intersect(n, f) → F
23. Polygon(C, D, F) → poly2, f_1, c_1, d_2
24. Intersect(p, a) → G
25. Polygon(P, P_x, G) → poly3, g_1, p_1, p_x