边长与三角形（一）：三角形构造与边长关系探究
2014-03-14 07:48
本GeoGebra范例演示三角形的构造及其边长之间的关系。通过点、线段、多边形、单位正交向量和单位向量等几何对象，动态展示等腰三角形和直角三角形的性质。用户可通过交互操作观察三角形边长变化对角度的影响，探索三角形不等式及几何变换下的边长守恒规律，适合中学几何教学与探究学习。
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