全等弦与圆心距离
几何画板及绘图内容加载中,请稍等……
①本范例演示了在圆内绘制两条全等弦时,这两条弦到圆心的距离相等的现象;②涉及的核心数学概念包括圆、全等、距离、几何作图;③作图要点——使用了Circle(圆)、Point(点)、Segment(线段)、Intersect(交点)、Midpoint(中点)、Angle(角度)、CircleSector(扇形)、Dilate(缩放)、Line(直线)、Vector(向量)、Translate(平移)、Rotate(旋转)等GeoGebra命令/对象;④适合高中数学教学,用于探究圆的性质和几何变换。
GeoGebra 命令及参数
Circle(A, B) → cPoint(c) → CSegment(A, C) → aPoint(c) → DPoint(c) → ECircle(D, Chord) → eCircle(E, Chord) → fIntersect(c, e, 1) → FIntersect(c, f, 1) → GSegment(G, E) → gSegment(D, F) → hMidpoint(g) → HMidpoint(h) → ISegment(A, H) → bSegment(A, I) → dAngle(A, I, D) → αAngle(G, H, A) → βCircle(I, (0.1 * g)) → kCircle(H, (0.1 * g)) → pIntersect(k, c, 1) → JIntersect(k, c, 1) → KIntersect(c, h, 2) → LIntersect(k, c, 1) → MIntersect(k, h) → N, OIntersect(p, g) → P, QIntersect(k, d, 1) → RIntersect(p, b, 1) → SCircleSector(I, O, R) → qCircleSector(H, P, S) → rDilate(E, If[0 < i ≤ 1, 1 - i, 0], G) → E'Dilate(D, If[0 < i ≤ 1, 1 - i, 0], L) → D'Segment(E, E') → jSegment(D, D') → lLine(D, j) → mPoint(m) → TAngle(F, D, T) → γDilate(G, If[1 < i ≤ 2, 2 - i, 0], D) → G'Vector(G, G') → uTranslate(E, u) → E'_1Translate(E', u) → E''Segment(E'_1, E'') → j'Rotate(E'_1, If[2 < i < 3, ((-(i - 2)) * γ), (-γ)], D) → URotate(E'', If[2 < i < 3, ((-(i - 2)) * γ), (-γ)], D) → E'''Segment(U, E''') → j''Dilate(A, If[3 < i ≤ 4, 4 - i, 0], H) → A'Dilate(A, If[3 < i ≤ 4, 4 - i, 0], I) → A'_1Segment(A, A') → nSegment(A, A'_1) → sRotate(r, If[4.5 < i < 5.5, ((i - 4.5) * π / 2), π / 2], H) → r'Rotate(q, If[5.5 < i < 6.5, ((i - 5.5) * π / 2), π / 2], I) → q'Angle(H, A, I) → δRotate(A, If[7 < i < 8, ((i - 7) * δ), δ], A) → A'_2Rotate(A', If[7 < i < 8, ((-(i - 7)) * ((2 * π) - δ)), δ - (2 * π)], A) → A''Segment(A'_2, A'') → n'