等腰三角形的外接圆动画
几何画板及绘图内容加载中,请稍等……
这个范例演示了等腰三角形的外接圆动画。涉及的核心数学概念包括等腰三角形的性质、外接圆、对称性等。作图要点包括使用Circle命令绘制圆,使用Intersect命令求交点,使用Dilate和Rotate命令进行变换,使用Segment命令绘制线段。适合初中及以上学生学习几何作图和变换。
GeoGebra 命令及参数
Circle(A, B_1) → cIntersect(c, q) → O, P_1CircleArc(A, O, P_1) → dPoint(d) → CLineBisector(C, A) → i_1Segment(A, C) → bPoint(b) → QLineBisector(A, Q) → n_1Segment(A, Q) → nCircleArc(A, C, P_1) → ePoint(e) → BLineBisector(A, B) → h_1Intersect(h_1, i_1) → UCircle(B, n) → tSegment(B, A) → gIntersect(t, g) → P,LineBisector(A, P) → r_1Intersect(r_1, n_1) → VAngle(A, V, U) → δDilate(V, If[12 < j ≤ 13, 13 - j, 0], A) → V'Dilate(A, If[0 < j ≤ 1, 1 - j, 0], C) → A'Segment(A, A') → aAngle(C, A, B) → αRotate(A, If[1 < j ≤ 2, ((j - 1) * α), α], A) → A'_1Rotate(A', If[1 < j ≤ 2, ((j - 1) * α), α], A) → A''Segment(A'_1, A'') → a'Segment(C, B) → fMidpoint(f) → ESegment(A, E) → hMidpoint(h) → FSegment(A, F) → iSegment(F, E) → kCircle(A, (0.35 * i)) → pCircle(E, (0.15 * Distance[B, E])) → rIntersect(r, f, 2) → GIntersect(r, h, 1) → HIntersect(r, f, 1) → IIntersect(p, b, 1) → JIntersect(p, h, 1) → KIntersect(p, g, 1) → LCircle(A, B_1) → c_1Dilate(C, If[2 < j ≤ 3, 3 - j, 0], B) → C'Segment(C, C') → lPolygon(C, B, A) → poly1, a_1, c_2, d_1Circle(C, (0.2 * Distance[B, E])) → e_1Intersect(e_1, b) → M,Intersect(e_1, f) → N,Dilate(A, If[3 < j ≤ 4, 4 - j, 0], F) → A'_2Dilate(F, If[5 < j ≤ 6, 6 - j, 0], E) → F'Dilate(E, If[6 < j ≤ 7, 7 - j, 0], B) → E'Rotate(E, If[7 < j ≤ 8, ((j - 7) * π), 3.141592653589793], E) → E'_1Rotate(E', If[7 < j ≤ 8, ((j - 7) * π), 3.141592653589793], E) → E''Dilate(C, If[9 < j ≤ 10, 10 - j, 0], B) → C'_1Vector(C, C'_1) → uAngle(E, C, A) → βSegment(C, B) → mIntersect(t, c, 1) → RDilate(A, If[4 < j ≤ 5, 5 - j, 0], Q) → A'_3Segment(A, A'_3) → sDilate(A, If[5 < j ≤ 6, 6 - j, 0], B) → A'_4Vector(A, A'_4) → vTranslate(A, v) → A'_5Translate(A'_3, v) → DSegment(A'_5, D) → s'Line(C, A) → f_1Line(B, f_1) → g_1Point(g_1) → SAngle(A, B, S) → γRotate(A'_5, If[6 < j ≤ 7, ((-(j - 6)) * γ), (-γ)], B) → TRotate(D, If[6 < j ≤ 7, ((-(j - 6)) * γ), (-γ)], B) → D'Segment(T, D') → s''Dilate(U, If[7 < j ≤ 8, 8 - j, 0], B) → U'Segment(U, U') → j_1Rotate(B, If[8 < j ≤ 9, (((j - 8) * 2) * π), (2 * π)], U) → B'Rotate(U, If[8 < j ≤ 9, (((j - 8) * 2) * π), (2 * π)], U) → U'_1Rotate(U', If[8 < j ≤ 9, (((j - 8) * 2) * π), (2 * π)], U) → U''Segment(U'_1, U'') → k_1CircleArc(U, B, B') → p_1Polygon(Q, P, A) → poly2, a_2, q_1, p_2Polygon(C, B, P, Q) → poly3, c_3, b_1, p_3, q_2Dilate(Q, If[9 < j ≤ 10, 10 - j, 0], P) → Q'Segment(Q, Q') → l_1Dilate(P, If[10 < j ≤ 11, 11 - j, 0], A) → P'Segment(P, P') → m_1Segment(V, V') → s_1Rotate(A, If[13 < j ≤ 14, (((j - 13) * 2) * π), (2 * π)], V) → A'_6Rotate(V, If[13 < j ≤ 14, (((j - 13) * 2) * π), (2 * π)], V) → V'_1Rotate(V', If[13 < j ≤ 14, ((j - 13) * δ), δ], V) → V''Segment(V'_1, V'') → t_1Circle(U, B) → e_2Circle(V, P) → f_2CircleArc(V, A, V'') → d_2Rotate(U_3, If[14 < j ≤ 15, ((j - 14) * ((2 * π) - δ)), (2 * π) - δ], V) → WCircleArc(V, U_3, W) → g_2Rotate(V'_1, If[14 < j ≤ 15, ((j - 14) * ((2 * π) - δ)), (2 * π) - δ], V) → ZRotate(V'', If[14 < j ≤ 15, ((j - 14) * ((2 * π) - δ)), (2 * π) - δ], V) → V'''Segment(Z, V''') → h_2