动态圆的问题演示
几何画板及绘图内容加载中,请稍等……
①这个范例动态演示了一个与圆相关的几何问题;②涉及的核心数学概念包括圆、交点、相似三角形和变换;③作图要点使用了Circle, PointIn, Intersect, Line, CircleArc, Point, Dilate, Segment, Angle, Vector, Translate, Polygon等GeoGebra命令;④适合高中数学教学和几何作图学习。
GeoGebra 命令及参数
Circle(O, B_1) → cPointIn(a) → ESemicircle(O, E) → dIntersect(c, d, 1) → ALine(E, A) → fSemicircle(E, O) → eIntersect(c, e, 1) → E_1CircleArc(O, A, E_1) → gPoint(g) → DLine(E, D) → hLine(A, O) → iIntersect(c, i, 2) → BLine(E, O) → jIntersect(c, h, 1) → CLine(B, C) → kIntersect(j, k) → FLine(B, D) → lIntersect(j, l) → GDilate(O, If[0 < b ≤ 1, 1 - b, 0], A) → O'Dilate(E, If[0 < b ≤ 1, 1 - b, 0], A) → E'Segment(O, O') → mSegment(E, E') → nAngle(O, A, E) → αDilate(O, If[0 < b ≤ 1, 1 - b, 0], B) → O'_1Segment(O, O'_1) → pDilate(E, If[2 < b ≤ 3, 3 - b, 0], C) → E'_1Segment(E, E'_1) → qDilate(C, If[3 < b ≤ 4, 4 - b, 0], D) → C'Segment(C, C') → rDilate(E, If[4 < b ≤ 5, 5 - b, 0], F) → E'_2Segment(E, E'_2) → sIntersect(c, j) → H, IDilate(F, If[5 < b ≤ 6, 6 - b, 0], I) → F'Segment(F, F') → tDilate(B, If[7 < b ≤ 8, 8 - b, 0], G) → B'Segment(B, B') → f_1Dilate(G, If[8 < b ≤ 9, 9 - b, 0], D) → G'Segment(G, G') → g_1Dilate(B, If[9 < b ≤ 10, 10 - b, 0], F) → B'_1Segment(B, B'_1) → h_1Dilate(F, If[10 < b ≤ 11, 11 - b, 0], C) → F'_1Segment(F, F'_1) → i_1Dilate(G, If[11 < b ≤ 12, 12 - b, 0], A) → G'_1Vector(G, G'_1) → uTranslate(B, u) → B'_2Translate(B', u) → B''Segment(B'_2, B'') → j_1Dilate(F, If[12 < b ≤ 13, 13 - b, 0], A) → F'_2Vector(F, F'_2) → vTranslate(B, v) → B'_3Translate(B'_1, v) → JSegment(B'_3, J) → k_1Polygon(G, B, F, A) → q1, g_2, b_1, f_2, a_1