余弦定理探索 by ms.amara2015

余弦定理探索 by ms.amara2015
几何画板及绘图内容加载中,请稍等……
2015-10-11 15:45
这个范例通过动态几何图形展示了余弦定理。它涉及三角形中的角度和边长关系。通过使用GeoGebra命令如Circle, Line, Intersect, Rotate, Angle, Segment等,可以直观地观察到当三角形的边长和角度变化时,余弦定理如何保持不变。适合高中数学教学和学习,特别是解析几何和三角函数部分。

GeoGebra 命令及参数

  1. Circle(IncludedAngle, Left) → c
  2. Circle(IncludedAngle, Bottom) → d
  3. Line(IncludedAngle, A) → a
  4. Intersect(d, a, 2) → SecondAngle
  5. Rotate(SecondAngle, Angle1, IncludedAngle) → B'
  6. Angle(SecondAngle, IncludedAngle, B') → α
  7. Line(IncludedAngle, B') → b
  8. Intersect(c, b, 2) → ThirdAngle
  9. Segment(IncludedAngle, SecondAngle) → BottomSide
  10. Segment(IncludedAngle, ThirdAngle) → LeftSide
  11. Segment(ThirdAngle, SecondAngle) → UnknownSide
  12. Angle(ThirdAngle, SecondAngle, IncludedAngle) → β
  13. Angle(IncludedAngle, ThirdAngle, SecondAngle) → γ
  14. Segment(ThirdAngle, SecondAngle) → e