三角形折叠构造与二次方程探究
几何画板及绘图内容加载中,请稍等……
① 本范例演示了通过折叠三角形(triangle 2 - folding)构造出新的几何图形,并利用折叠关系建立二次方程求解的过程。② 核心数学概念包括等边三角形、角平分线、垂直平分线、对称变换、二次方程以及几何量的代数化。③ 作图要点:从构造摘要可见,使用了多边形(Polygon)、线段(Segment)、中点(Midpoint)、旋转(Rotate)、圆弧(CircleArc)、交点(Intersect)、角平分线(AngularBisector)、正交线(OrthogonalLine)、镜像(Mirror)、圆(Circle)和直线(Line)等GeoGebra命令,并创建了多个辅助点(如E、F、G)及折叠后的像点(E'、D'、G'),通过动态几何探索折叠前后图形的关系。④ 适合学段:适用于初中高年级或高中阶段,用于几何与代数结合的教学,也可作为数学建模或探究性学习的素材。
GeoGebra 命令及参数
Polygon(A, C, D, B) → vierhoek1, a, c, d, bSegment((sqrt(2) / 4, 0), (sqrt(2) / 4, 1)) → fSegment((sqrt(2) / 2, 0), (sqrt(2) / 2, 1)) → gSegment(((3 * sqrt(2) / 4), 0), ((3 * sqrt(2) / 4), 1)) → hMidpoint(B, D) → ERotate(D, -90°, E) → DDCircleArc(E, DD, D) → eIntersect(e, h, 1) → FCircleArc(E, F, D) → kAngularBisector(F, E, D) → iIntersect(i, c) → GSegment(E, G) → jPolygon(A, C, G, E, B) → veelhoek1, a_1, c_1, g_1, e_1, b_1Polygon(E, D, G) → driehoek1, g_2, e_2, d_1Rotate(E, (((-(s - 1)) * 180))°, g_1) → E'Rotate(D, (((-(s - 1)) * 180))°, g_1) → D'Rotate(G, (((-(s - 1)) * 180))°, g_1) → G'Polygon(E', D', G') → driehoek1', g', e', d'Polygon(E, F, G) → driehoek2, g_3, e_3, f_1Segment(E, D) → lSegment(D, G) → mOrthogonalLine(F, a_1) → nIntersect(j, d') → HHIntersect(j, d') → IIIntersect(n, j) → RIntersect(n, a_1) → SSegment(R, S) → pSegment(F, S) → qMirror(F, g) → HMirror(G, g) → ISegment(I, E) → rCircleArc(E, B, H) → tPolygon(I, E, B) → driehoek3, b_2, i_1, e_4Rotate(I, (((s - 3) * 180))°, r) → I'Rotate(E, (((s - 3) * 180))°, r) → E'_1Rotate(B, (((s - 3) * 180))°, r) → B'Polygon(I', E'_1, B') → driehoek3', b', i', e'_1Polygon(E, I, A, C, G) → veelhoek2, e_5, i_2, a_2, c_2, g_4Segment(B, E) → h_1Segment(B, I) → j_1Mirror(R, g) → TTMirror(S, g) → SSSegment(SS, TT) → k_1Segment(SS, H) → l_1Polygon(I, H, E) → driehoek4, e_6, i_3, h_2Circle(G, C) → p_1Intersect(d', f_1) → JIntersect(d', f_1) → KIntersect(d', f_1) → LIntersect(d', f_1) → MIntersect(p_1, f_1) → N,CircleArc(G, N, C) → q_1Line(G, F) → m_1Intersect(m_1, a_2) → OSegment(O, F) → n_1Polygon(O, C, G) → driehoek5, g_5, o, c_3Rotate(O, (((s - 5) * 180))°, c_3) → O'Rotate(C, (((s - 5) * 180))°, c_3) → C'Rotate(G, (((s - 5) * 180))°, c_3) → G'_1Polygon(O', C', G'_1) → driehoek5', g'_1, o', c'Polygon(I, A, O, G, E) → veelhoek3, i_4, a_3, o_1, g_6, e_7Mirror(O, n_1) → O'_1Mirror(C, n_1) → C'_1Mirror(G, n_1) → G'_2Polygon(O'_1, C'_1, G'_2) → driehoek5'_1, g'_2, o'_1, c'_1Mirror(O, g) → O'_2Mirror(C, g) → C'_2Mirror(G, g) → G'_3Polygon(O'_2, C'_2, G'_3) → driehoek5'_2, g'_3, o'_2, c'_2Rotate(O, (((s - 5) * 180))°, c_3) → O'_3Rotate(G, (((s - 5) * 180))°, c_3) → G'_4Rotate(O'_2, (((-(s - 6)) * 180))°, c'_2) → QRotate(G'_3, (((-(s - 6)) * 180))°, c'_2) → UIntersect(c', o_1) → VIntersect(c', o_1) → WIntersect(c', o_1) → ZLine(I, H) → r_1Intersect(o_1, r_1) → TSegment(O, C) → s_1Segment(C, G) → t_1Polygon(I, A, O, T) → vierhoek2, i_5, a_4, o_2, t_2Rotate(I, (((-(s - 7)) * 180))°, t_2) → I'_1Rotate(A, (((-(s - 7)) * 180))°, t_2) → A'Rotate(O, (((-(s - 7)) * 180))°, t_2) → O'_4Rotate(T, (((-(s - 7)) * 180))°, t_2) → T'Polygon(I, T, G, E) → vierhoek3, i_6, t_3, g_7, e_8Segment(E, T) → f_2Segment(T, E) → j_2Intersect(Segment[O, N], j_2) → A_1Segment(A_1, E) → k_2Rotate(I, (((-(s - 7)) * 180))°, i_6) → I'_2Rotate(A, (((-(s - 7)) * 180))°, i_6) → A'_1Rotate(O, (((-(s - 7)) * 180))°, i_6) → O'_5Rotate(T, (((-(s - 7)) * 180))°, i_6) → T'_1Polygon(I'_2, A'_1, O'_5, T'_1) → vierhoek2', i'_2, a'_1, o'_5, t'_1Mirror(N, g) → NNCircleArc(I, A, NN) → d_2Segment(I, T) → l_2Intersect(g'_2, l_2) → B_1Polygon(N, B_1, T, G) → vierhoek4, n_2, b_3, t_4, g_8Segment(I, A) → m_2Segment(A, O) → p_2Midpoint(B, E) → C_1Midpoint(I, G) → D_1Midpoint(E, D) → E_1Mirror(O, l_2) → OOMirror(A, l_2) → AAPolygon(I, T, OO, AA) → vierhoek5, i_7, t_5, oo, aaSegment(B_1, OO) → s_2Intersect(i_3, oo) → F_1Polygon(F_1, OO, E) → driehoek6, e_9, f_3, oo_1Polygon(E, T, G) → driehoek7, g_9, e_{10}, t_6Rotate(E, (((-(s - 9)) * 180))°, g) → E'_2Rotate(T, (((-(s - 9)) * 180))°, g) → T'_2Rotate(G, (((-(s - 9)) * 180))°, g) → G'_5Polygon(E'_2, T'_2, G'_5) → driehoek7', g'_5, e'_2, t'_2Segment(E, T) → h_3Segment(OO, E) → j_3Polygon(I, T, E) → driehoek8, e_{11}, i_8, t_7OrthogonalLine(I, e_6) → q_2OrthogonalLine(G, e_3) → r_2Intersect(r_2, q_2) → G_1CircleArc(G_1, I, G) → d_3
AI 绘图提示语参考
画一个等边三角形,然后在其内部构造一个几何折叠问题。首先,从三角形的一个顶点出发,绘制三条线段,分别代表折叠后的新形状。接着,找到线段的中点,并以此为基础绘制圆弧和角平分线。利用这些线段和圆弧,找到交点并构造新的三角形。然后,将新三角形进行旋转和镜像操作,模拟折叠过程。最后,绘制辅助线段和辅助图形,展示折叠前后形状的对应关系和几何量之间的代数表示。
以上提示语为根据原始绘图命令整理而来,仅供参考。