证明三角形相似(3)
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本范例演示如何通过角度和边长关系证明三角形相似。涉及的核心数学概念包括三角形相似判定定理、角度相等和边长比例。作图要点包括使用射线、旋转、角度、点、线段、多边形、向量、平移和缩放等 GeoGebra 命令。适合高中数学教学和几何作图练习。
GeoGebra 命令及参数
Ray(D, E) → f_2Rotate(E, (a_3 * π / 180), D) → B'Angle(E, D, B') → αRay(D, B') → gPoint(g) → FSegment(F, E) → dSegment(D, E) → fPolygon(D, E, F) → poly1, c_2, a_1, b_2Segment(D, F) → eAngle(F, E, D) → βVector(D_1, E_1) → uPolygon(D, E, F) → poly2, c_1, a_2, b_1Translate(D, u) → A'Translate(E, u) → B'_1Translate(F, u) → C'Polygon(A', B'_1, C') → poly2', c', a', b'_1Dilate(A', d_1, A') → A''Dilate(B'_1, d_1, A') → F_1Dilate(C', d_1, A') → CPolygon(A'', F_1, C) → poly2'', c'', a'', f_1Segment(A', C) → kSegment(C, F_1) → lSegment(F_1, A') → mRotate(A'', (e_1 * π / 180), C) → A'''Rotate(F_1, (e_1 * π / 180), C) → BRotate(C, (e_1 * π / 180), C) → C'''Polygon(A''', B, C''') → poly2''', c''', a_4, f'Rotate(A', (e_1 * π / 180), C) → ASegment(A, B) → cSegment(B, C) → aSegment(C, A) → b