菱形的面积 by mathspace

GeoGebra 命令及参数

1. Segment(A, B) → a
2. LineBisector(a) → b
3. Intersect(b, a) → C
4. Point(b) → D
5. Circle(C, D) → c
6. Intersect(c, b, 2) → E
7. Polygon(A, C, E) → poly2, e_1, a_2, c_1
8. Polygon(C, B, E) → poly3, e_2, c_2, b_2
9. Polygon(D, A, B) → poly1, b_1, d, a_1
10. Vector(A, ((r * x(D)), (r * y(D)))) → u
11. Translate(A, u) → A'
12. Translate(C, u) → C'_1
13. Translate(E, u) → E'_1
14. Polygon(A', C'_1, E'_1) → poly2', e', a', c'
15. Line(D, B) → e
16. Translate(B, u) → B'_1
17. Vector(B, B'_1) → v
18. OrthogonalLine(B, d) → f
19. Mirror(B'_1, f) → B''
20. Vector(B, B'') → w
21. Translate(C, w) → C'
22. Translate(B, w) → B'
23. Translate(E, w) → E'
24. Polygon(C', B', E') → poly3', e'_1, c'_1, b'
25. Segment(D, C) → g
26. OrthogonalLine(F, b') → h
27. Circle(F, (0.1 * b')) → k
28. Intersect(k, h) → G, H
29. Line(H, b') → i
30. Circle(H, (0.5 * b')) → p
31. Intersect(p, i) → I, J
32. Vector(H, J) → z
33. Vector(H, I) → j
34. Circle(D, (0.1 * b')) → q
35. Intersect(q, b) → K, L
36. Line(L, e') → l
37. Circle(L, e') → s
38. Intersect(s, l) → M, N
39. Vector(L, M) → m
40. Vector(L, N) → n
41. Intersect(a_1, b_1) → O
42. Intersect(c', a') → P
43. Point(a) → Q
44. Intersect(a, a_1) → R
45. Segment(Q, R) → d_1
46. Line(A, B) → f_1
47. Line(D, f_1) → g_1
48. Translate(D, w) → D'
49. OrthogonalLine(E', g_1) → h_1
50. Intersect(g_1, h_1) → T
51. Segment(T, E') → t
52. Length(Segment[D, E]) → i_1