余弦定理演示-钝角三角形

GeoGebra 命令及参数

1. Line(B, C) → s
2. OrthogonalLine(C, s) → t
3. Point(t) → S
4. Polygon(S, C, 4) → poly12, s_1, c_5, f_1, k_1, T, U
5. Polygon(B, C, 4) → poly1, b_2, c_3, a_3, d, G_1, D_1
6. PointIn(poly12) → A
7. Polygon(A, B, C) → poly3, c, a, b
8. Angle(A, C, B) → α
9. Polygon(A, C, 4) → poly4, a_2, c_2, g, h, D, E
10. Midpoint(A, D) → F
11. Line(B, c_2) → i
12. Line(D, a) → j
13. Intersect(i, j) → G
14. OrthogonalLine(B, c) → k
15. Polygon(D, G, 4) → poly5, d_1, g_1, l, m, H, I
16. Line(I, g) → n
17. Line(E, m) → p
18. Intersect(n, p) → J
19. Polygon(I, J, E, D) → poly6, i_1, j_1, e_1, d_2
20. Polygon(G, D, C, B) → poly7, g_2, d_3, c_4, b_1
21. Polygon(H, G, B) → poly8, b_3, h_1, g_3
22. Midpoint(G, I) → K
23. Angle(B, G, H) → β
24. Midpoint(B, D) → L
25. Midpoint(D, J) → M
26. Vector(N, O) → u
27. Translate(B, u) → B'
28. Translate(H, u) → H'
29. Translate(I, u) → I'
30. Translate(J, u) → J'
31. Translate(E, u) → E'
32. Translate(A, u) → A'
33. Polygon(A', B', 4) → poly9, a', b', q, r, P, Q
34. Polygon(H', I', J') → poly10, j', h', i'
35. Polygon(J', E', A') → poly11, a'_1, j'_1, e'
36. Midpoint(B', J') → R
37. Angle(J', I', H') → γ
38. Angle(A', E', J') → δ