正五边形到正方形的剖分变换
几何画板及绘图内容加载中,请稍等……
① 本范例演示如何将一个正五边形通过几何剖分与平移变换,重新拼合成一个面积相等的正方形,直观展示等面积变换的构造过程。② 核心数学概念包括多边形剖分、面积守恒、平移变换以及几何作图;涉及正五边形与正方形的边长关系,体现几何直观与代数计算结合。③ 作图要点:从构造摘要看,使用了GeoGebra的Point、Polygon、Segment、Intersect、OrthogonalLine、Midpoint、Circle、Line、If、Vector、Translate等命令,创建了多个辅助点、线、圆和向量,通过平移将剖分后的五边形部分重新排列成正方形,涉及对象如A、B、poly1、f、g、h、i、j、C、D、E等,以及多个辅助线和圆。④ 适合中学几何教学、数学竞赛或师范生几何变换专题,可用于探究等面积剖分与动态几何演示。
GeoGebra 命令及参数
Point(xAxis) → APoint(xAxis) → BPolygon(A, B, 5) → poly1, f, g, h, i, j, C, D, ESegment(E, C) → kSegment(D, A) → lIntersect(k, l) → FOrthogonalLine(D, f) → mIntersect(m, f) → GSegment(D, G) → nMidpoint(n) → HOrthogonalLine(C, f) → pCircle(C, Segment[H, G]) → cIntersect(c, p, 1) → IOrthogonalLine(I, p) → qIntersect(q, j) → JOrthogonalLine(J, q) → rSegment(A, C) → sLine(J, s) → tIntersect(t, k) → KIntersect(q, g) → LOrthogonalLine(L, s) → aIntersect(t, a) → MPolygon(E, D, F) → t1, f_1, e, dPolygon(F, D, C) → t2, c_1, f_2, d_1Polygon(K, M, L, C) → q1, k_1, m_1, l_1, c_2Polygon(L, M, J, A, B) → poly2, l_2, m_2, j_1, a_1, bCircle(K, Segment[J, L]) → e_1Intersect(e_1, k, 1) → NOrthogonalLine(N, t) → g_1Intersect(t, g_1) → OPolygon(N, O, K) → t3, k_2, n_1, oPolygon(E, N, O, J) → q2, e_2, n_2, o_1, j_2OrthogonalLine(D, yAxis) → h_1Point(h_1) → PIf(0 ≤ u < 1, Dilate[M, 1 - u, P], P) → QVector(M, Q) → vTranslate(L, v) → L'Translate(M, v) → M'Translate(J, v) → J'Translate(A, v) → A'Translate(B, v) → B'Polygon(L', M', J', A', B') → poly2', l', m', j', a', b'If(2 ≤ u < 3, Dilate[C, 3 - u, B'], B') → RVector(C, R) → wTranslate(F, w) → F'Translate(D, w) → D'Translate(C, w) → C'Polygon(F', D', C') → t2', c', f', d'If(2 ≤ u < 3, Polygon[Rotate[F', (((u - 2) * 2) * π / 10), R], Rotate[D', (((u - 2) * 2) * π / 10), R], Rotate[C', (((u - 2) * 2) * π / 10), R]], Polygon[Rotate[F', (((3 - 2) * 2) * π / 10), R], Rotate[D', (((3 - 2) * 2) * π / 10), R], Rotate[C', (((3 - 2) * 2) * π / 10), R]]) → t4If(2 ≤ u < 3, Rotate[F', (((u - 2) * 2) * π / 10), R], Rotate[F', (((3 - 2) * 2) * π / 10), R]) → SIf(4 ≤ u < 5, Dilate[L, 5 - u, L'], L') → TVector(L, T) → u_1If(4 ≤ u < 5, Rotate[Polygon[Translate[K, u_1], Translate[M, u_1], Translate[L, u_1], Translate[C, u_1]], ((u - 4) * π), T], Rotate[Polygon[Translate[K, u_1], Translate[M, u_1], Translate[L, u_1], Translate[C, u_1]], π, T]) → q3If(4 ≤ u < 5, Rotate[Translate[K, u_1], ((u - 4) * π), T], Rotate[Translate[K, u_1], π, T]) → UIf(6 ≤ u < 7, Dilate[E, 7 - u, S], S) → VVector(E, V) → v_1If(6 ≤ u < 7, Polygon[Translate[E, v_1], Translate[D, v_1], Translate[F, v_1]], Polygon[Translate[E, v_1], Translate[D, v_1], Translate[F, v_1]]) → t5If(8 ≤ u < 9, Dilate[K, 9 - u, U], U) → WVector(K, W) → w_1If(8 ≤ u < 9, Polygon[Translate[N, w_1], Translate[O, w_1], Translate[K, w_1]], Polygon[Translate[N, w_1], Translate[O, w_1], Translate[K, w_1]]) → t6If(10 ≤ u ≤ 11, Dilate[J, 11 - u, J'], J') → ZVector(J, Z) → b_1If(10 ≤ u ≤ 11, Rotate[Polygon[Translate[E, b_1], Translate[N, b_1], Translate[O, b_1], Translate[J, b_1]], ((u - 10) * π), Z], Rotate[Polygon[Translate[E, b_1], Translate[N, b_1], Translate[O, b_1], Translate[J, b_1]], ((11 - 10) * π), Z]) → q4
AI 绘图提示语参考
画一个正五边形,并展示如何通过平移分割它的部分,使其重新组合成一个面积相等的正方形。首先绘制正五边形,然后找到关键点并绘制辅助线、圆和向量。接着,将五边形分割成几块,通过平移这些碎片,使其形成一个新的正方形。整个过程中,注意保持面积不变,并展示平移变换的细节。
以上提示语为根据原始绘图命令整理而来,仅供参考。