RHS三角形全等条件动态几何构造
2021-07-30 15:38
本GeoGebra范例演示RHS（直角-斜边-边）三角形全等条件的几何构造过程。通过Point、Vector、Segment、Polygon、Angle等命令构建点A、B、C、D、E、F及向量u、v，利用Sequence和DynamicCoordinates实现动态坐标序列生成，结合Intersect求交与If条件判断，展示两个直角三角形在满足RHS条件时的全等关系。角度α和β的标注辅助说明对应角相等，多边形填充与线段构造直观呈现几何证明逻辑，适合中学几何教学与全等三角形判定定理的可视化探究。
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<command name="If">
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<expression label="text1" exp=""拖拉紅點，構作一個滿足以下條件的著色的△PQR：
PR = AC, PQ = AB, ∠Q = ∠B = 90°。
△PQR 是否必定全等於 △ABC？ ""/>
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<element type="segment" label="e">
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<command name="Angle">
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<output a0="β"/>
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<element type="angle" label="β">
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<value val="1.5707963267948966"/>
<show object="true" label="false" ev="4"/>
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<lineStyle thickness="5" type="0" typeHidden="2" opacity="178"/>
<arcSize val="50"/>
</element>
</construction>
</geogebra>