经典最大体积长方体可视化
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本示例演示如何通过调整滑块 g、h 和高度来改变长方体的尺寸,从而观察其体积的变化。核心数学概念包括立体几何和导数。使用了 Intersect、Polygon、Mirror、If、Vector、Derivative、Midpoint、Max、Name 等 GeoGebra 命令。适合高中数学教学和学习。
GeoGebra 命令及参数
Intersect(xAxis, yAxis) → DPolygon(D, A, C, B) → poly1, d, a, c, bPolygon(D, F, E, G) → poly2, d_1, f, e, g_1Mirror(D, x = Segment[D, A] / 2) → D'Mirror(F, x = Segment[D, A] / 2) → F'Mirror(E, x = Segment[D, A] / 2) → E'Mirror(G, x = Segment[D, A] / 2) → G'Polygon(D', F', E', G') → poly2', d', f', e', g'Mirror(D, y = Segment[D, B] / 2) → D'_1Mirror(A, y = Segment[D, B] / 2) → A'Mirror(C, y = Segment[D, B] / 2) → C'Mirror(B, y = Segment[D, B] / 2) → B'Mirror(D, y = Segment[D, B] / 2) → D'_2Mirror(F, y = Segment[D, B] / 2) → F'_1Mirror(E, y = Segment[D, B] / 2) → E'_1Mirror(G, y = Segment[D, B] / 2) → G'_1Polygon(D'_2, F'_1, E'_1, G'_1) → poly2'_1, d'_2, f'_1, e'_1, g'_1If(Segment[D, B] ≥ Segment[D, A], Segment[D, A] / 2, Segment[D, B] / 2) → maxvalIf(Segment[D, B] ≥ Segment[D, A], maxval = Segment[D, A] / 2, maxval = Segment[D, B] / 2) → iMirror(D', y = Segment[A, C] / 2) → D''Mirror(F', y = Segment[A, C] / 2) → F''Mirror(E', y = Segment[A, C] / 2) → E''Mirror(G', y = Segment[A, C] / 2) → G''Polygon(D'', F'', E'', G'') → poly2'', d'', f'', e'', g''Polygon(E'_1, E'', E', E) → poly3, e'_2, e''_1, e'_3, e_1Vector(H, I) → uDerivative(V) → pMidpoint(D, F) → dfavgMax(V, 0, maxval) → JMax(V, 0, maxval) → maxofvName(height) → A1