武汉二中2018年分配生考试第23题第(3)问几何旋转与作图探究
2020-05-28 04:51
本范例演示了武汉市第二中学2018年分配生考试数学第23题第(3)问的几何构造与动态探究过程。通过GeoGebra软件,利用线段、角、圆、正交线及交点等基础几何对象,结合旋转、缩放等几何变换,直观展示了题目中复杂的几何图形关系与动态变化规律。该范例有助于学生深入理解平面几何中的旋转性质、辅助线作法以及动点轨迹问题,提升几何直观与逻辑推理能力。
所属专题
武汉市分配生考试
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<expression label="text6" exp=""∵sin∠EMP=\frac{12}{13} \\∴设EP=12a,则EM=13a,PM=5a,""/>
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<condition showObject="t ≥ 1"/>
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<expression label="text7" exp=""∵EM=EN ∴EN=13a,PN=5a,""/>
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<condition showObject="t ≥ 2"/>
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<expression label="text8" exp=""∵ΔAEP∽ΔABC,∴\frac{PE}{AP}=\frac{BC}{AC}\\∴AP=16a=x,BN=50-21a=y""/>
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<show object="true" label="false" ev="40"/>
<condition showObject="t ≥ 3"/>
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<expression label="text9" exp=""∴y=50-\frac{21}{16}x""/>
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<condition showObject="t ≥ 4"/>
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<expression label="text10" exp=""∵当E与C重合时,AP=\sqrt{AC^2-CP^2} =32 \\∴0<x<32""/>
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<condition showObject="t ≥ 5"/>
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