相似直角三角形演示 by Philip Taylor
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①本范例演示相似直角三角形的构造与性质;②涉及核心数学概念包括相似三角形判定、直角三角形特性、角度与边长关系、面积计算及百分比;③构造要点:使用Line, OrthogonalLine, Point, Polygon, Intersect, Segment, Angle, Rotate, Mirror, Vector, Translate等命令创建和变换图形;④适合高中数学教学,用于理解相似性与几何变换。
GeoGebra 命令及参数
Line(A, B) → fOrthogonalLine(A, f) → gPoint(g) → CPolygon(B, A, C) → t1, c, b, aOrthogonalLine(A, a) → hIntersect(h, a) → DSegment(A, D) → iPolygon(A, D, B) → t2, b_1, a_1, dPolygon(D, A, C) → t3, c_1, d_1, a_2Angle(C, D, A) → αAngle(D, B, A) → βAngle(A, D, B) → γAngle(D, A, C) → δAngle(A, C, D) → εAngle(B, A, D) → ζRotate(D, ((-t) * (π - β)), A) → D'Rotate(A, ((-t) * (π - β)), A) → A'Rotate(C, ((-t) * (π - β)), A) → C'Polygon(D', A', C') → t3', c', d', a'Rotate(D, ((-t) * (π - β)), A) → D'_1Rotate(A, ((-t) * (π - β)), A) → A'_1Rotate(C, ((-t) * (π - β)), A) → C'_1Polygon(D'_1, A'_1, C'_1) → t3'_1, c'_1, d'_1, a'_1Rotate(A, (t * (π / 2 + β)), B) → A'_2Rotate(D, (t * (π / 2 + β)), B) → D'_2Rotate(B, (t * (π / 2 + β)), B) → B'Polygon(A'_2, D'_2, B') → t2', b', a'_2, d'_2Line(C, c) → jMirror(B, j) → B'_1Mirror(A, j) → A'_3Mirror(C, j) → C'_2Rotate(B'_1, (t * π / 2), C) → ERotate(A'_3, (t * π / 2), C) → FRotate(C'_2, (t * π / 2), C) → GPolygon(E, F, G) → t1'', g_1, e, f_1Vector(D'_2 - F) → uVector(D'_1 - F) → vTranslate(A'_2, Vector[((-k) * u)]) → HTranslate(D'_2, Vector[((-k) * u)]) → ITranslate(B', Vector[((-k) * u)]) → B''Polygon(H, I, B'') → t2'', b'', h_1, i_1Translate(D', Vector[((-k) * v)]) → D''Translate(A', Vector[((-k) * v)]) → A''Translate(C', Vector[((-k) * v)]) → C''Polygon(D'', A'', C'') → t3'', c'', d'', a''Angle(C'', D'', A'') → θAngle(G, F, E) → ιAngle(F, E, G) → κAngle(D'', A'', C'') → λAngle(I, B'', H) → μAngle(B'', H, I) → νAngle(A'', C'', D'') → ξAngle(E, G, F) → ο