等腰梯形的性质 by Alfred Estberg

GeoGebra 命令及参数

1. Segment(A, B) → a
2. Segment(D, A) → b
3. LineBisector(a) → c
4. Mirror(D, c) → C
5. Segment(D, C) → d
6. Segment(C, B) → e
7. Segment(A, C) → f
8. Segment(B, D) → g
9. Intersect(f, g) → E
10. Mirror(B, f) → B'
11. Circle(B, (Distance[B, B'] * ReflectAC / 10)) → h
12. Intersect(h, Segment[B, B']) → F, G
13. Polygon(A, C, F) → poly1, j, l, m
14. Mirror(A, g) → A'
15. Circle(A, (Distance[A, A'] * ReflectBD / 10)) → k
16. Intersect(k, Segment[A, A']) → I, J
17. Polygon(D, B, J) → poly2, i, n, p
18. Polygon(A, B, C, D) → poly3, a_1, b_1, c_1, d_1
19. Rotate(A, α, E) → A'_1
20. Rotate(B, α, E) → B'_1
21. Rotate(C, α, E) → C'
22. Rotate(D, α, E) → D'
23. Polygon(A'_1, B'_1, C', D') → poly3', a'_1, b'_1, c', d'
24. Segment(A'_1, C') → q
25. Segment(B'_1, D') → r
26. OrthogonalLine(D, d) → s
27. OrthogonalLine(C, d) → t
28. Intersect(s, a) → H
29. Intersect(t, a) → K
30. Segment(H, K) → f_1
31. LineBisector(A, B) → g_1
32. Intersect(g_1, d) → L
33. Intersect(g_1, a) → M
34. Circle(A, (ReflectPerp * Segment[A, B])) → e_1
35. Circle(D, (ReflectPerp * Segment[C, D])) → h_1
36. Intersect(h_1, d, 1) → N
37. Intersect(e_1, a, 1) → O
38. Polygon(L, N, O, M) → q1, l_2, n_2, o, m_2
39. Intersect(h_1, d, 2) → P
40. Polygon(P, L, M, O) → q2, p_2, l_3, m_3, o_2
41. Polygon(D, B, I) → t1, i_2, d_2, b_2
42. Polygon(A, C, G) → t2, g_2, a_2, c_2