线面角的投影

GeoGebra 命令及参数

1. Sequence((0, (-cos(i°)), sin(i°)), i, 1, 179) → list2
2. Point(list2) → A
3. Sequence((x(A), y(A) - (0.5 * cos(i°)), z(A) + (0.5 * sin(i°))), i, 1, 179) → list1
4. Point(list1) → S
5. Rotate(S, phi, OrthogonalLine[A, xOyPlane]) → S'
6. CircumcircleArc((0, -1, 0), (0, 0, 1), (0, 1, 0)) → c
7. Intersect(xAxis, yAxis) → B
8. Segment(B, A) → a
9. Intersect(Ray[S', A], xOyPlane) → P
10. Segment(B, P) → p
11. Angle(A, P, B) → α
12. Angle(P, B, A) → β
13. Ray(P, S') → b
14. Translate(B, Vector[A, S']) → B'
15. Ray(B, B') → d
16. Midpoint(B, A) → D
17. Midpoint(B, P) → E
18. Ray(E, D) → g