无言证明 by Steve Phelps
几何画板及绘图内容加载中,请稍等……
拖动点A和B,观察图形的变化。这个范例通过动态几何展示了三角形的中线定理。它利用了点、交点、镜像、圆弧、线段、多边形、射线、重心、向量、平移等GeoGebra命令。适合初中及以上学生学习几何证明。
GeoGebra 命令及参数
Point(xAxis) → AIntersect(xAxis, yAxis) → BMirror(A, B) → A'CircleArc(B, C, A) → cPoint(c) → DSegment(A, D) → aSegment(D, A') → bSegment(A', A) → dPolygon(D, A', 4) → poly1, e, f, g, p, E, HRay(E, H) → sPolygon(A, D, 4) → poly3, k, l, m, q, G, JRay(J, G) → rRay(E, H) → tIntersect(r, t) → KPolygon(D, G, K) → poly4, k_1, d_1, g_1Polygon(D, H, K) → poly5, k_2, d_2, h_1Polygon(A, D, A') → poly6, a', a_1, d_3Centroid(poly4) → FCentroid(poly5) → ICentroid(poly6) → LVector(G, J) → uVector(H, E) → vTranslate(F, u) → F'Translate(I, v) → I'Segment(F, F') → hSegment(I, I') → iPoint(h) → MVector(F, M) → wPoint(i) → NVector(I, N) → jTranslate(D, j) → D'Translate(H, j) → H'Translate(K, j) → K'Polygon(D', H', K') → poly5', k', d', h'Translate(D, w) → D'_1Translate(G, w) → G'Translate(K, w) → K'_1Polygon(D'_1, G', K'_1) → poly4', k'_1, d'_1, g'Vector(D, K) → nTranslate(L, n) → L'Segment(L, L') → b_1Point(b_1) → OVector(L, O) → u_1Translate(A, u_1) → A'_1Translate(D, u_1) → D'_2Translate(A', u_1) → A''Polygon(A'_1, D'_2, A'') → poly6', a'', a'_1, d'_2Segment(A, A') → c_1Segment(E, K) → e_1Segment(G, K) → f_1