积极 AI Logo 积极 AI

梯形面积计算 by Jorge Cássio

梯形面积计算 by Jorge Cássio
几何画板及绘图内容加载中，请稍等……
2020-02-25 21:43
多边形三角函数几何作图
①本范例演示梯形面积的计算方法；②涉及核心数学概念包括梯形面积公式、几何作图、多边形构造；③作图要点：使用Segment, Line, Point, Polygon, Intersect, Circle, Rotate, Midpoint, OrthogonalLine等命令构建梯形及辅助图形；④适合初中及以上学生学习几何作图与面积计算，也可用于数学教学演示。

GeoGebra 命令及参数

  1. Segment(A, B) → Base
  2. Line(C, Base) → b
  3. Point(b) → D
  4. Point(b) → E_1
  5. Polygon(A, D, E_1, B) → pol1, a_1, d, e, b_1
  6. Line(A, e) → f
  7. Intersect(b, f) → G
  8. Intersect(b, d) → H
  9. Circle(E_1, B) → q
  10. Line(B, E_1) → n
  11. Intersect(q, n, 2) → K
  12. Rotate(B, spin, E_1) → B'
  13. Intersect(Base, b_1) → N
  14. Midpoint(e) → F
  15. Polygon(D, F, E_1) → pol2, e_1, d_1, f_1
  16. Polygon(A, B, F, D) → pol3, a, b_2, f_2, d_2
  17. Segment(D, E_1) → base
  18. Segment(F, E_1) → g
  19. Segment(D, F) → h
  20. Polygon(F, E_1, D) → pol4, d_3, f_3, e_2
  21. Rotate(F, (-spin), F) → F'
  22. Rotate(E_1, (-spin), F) → E
  23. Rotate(D, (-spin), F) → D'
  24. Polygon(F', E, D') → pol4', d', f', e'_1
  25. Segment(F, B) → j
  26. OrthogonalLine(D, Base) → k
  27. Intersect(k, Base) → I
  28. Segment(D, I) → l
  29. Segment(D', E) → base_1