用圆的分割与平移演示分数的加减
几何画板及绘图内容加载中,请稍等……
本范例通过对同分母圆盘进行分割、平移与叠加着色,直观展示分数在几何意义下如何相加与相减,以及结果如何由剩余部分得到。核心数学概念包括分数表示、同分母相加/相减的“部分—整体”思想、最小公倍数(LCM)与分子/分母的对应关系,用到的还有几何变换中的平移(Translate)以及向量(Vector)作为几何操作的参数。作图要点:利用 Circle 生成两类圆(如对象 centerR/radius 与 centerB/circleB 相关的圆),再用 LCM 计算公共分母,并配合 GCD/LCM 得到 LCMdenominator、LCMnumeratorR、LCMnumeratorB 等关键数值;通过 Vector 与 Translate 完成从一圆到另一圆的位移(对象如 tfactorB、shiftcircle、A/B/u/v 等),随后使用 cutR/cutB 与 cutLCMR/cutLCMB 将圆盘切割成可计数的分数部分,并用 shadeR/shadeB 与 cuttotal0/total0 对应显示相加或相减后的保留区域;最后可聚合生成 E~J 与 w、D、K 等中间构件并呈现 showfinal。适合中学阶段(分数运算与等值变形)以及数学可视化教学、复习课与探究式学习使用。
GeoGebra 命令及参数
Circle(centerR, radius) → circleRCircle(centerB, radius) → circleBLCM(denominatorR, denominatorB) → LCMdenominatorSequence(Segment[centerR, Rotate[AR, radius°, centerR]], radius, 360 / denominatorR, 360, 360 / denominatorR) → cutRSequence(Segment[centerB, Rotate[AB, radius°, centerB]], radius, 360 / denominatorB, 360, 360 / denominatorB) → cutBSequence(CircleSector[centerR, Rotate[AR, radius°, centerR], Rotate[AR, (radius + 360 / denominatorR)°, centerR]], radius, 0, 360 / denominatorR * numeratorR - 360 / denominatorR, 360 / denominatorR) → shadeRSequence(CircleSector[centerB, Rotate[AB, (-radius - 360 / denominatorB)°, centerB], Rotate[AB, (-radius)°, centerB]], radius, 0, 360 / denominatorB * numeratorB - 360 / denominatorB, 360 / denominatorB) → shadeBSequence(Segment[centerR, Rotate[AR, radius°, centerR]], radius, 0, 360, 360 / LCMdenominator) → cutLCMRSequence(Segment[centerB, Rotate[AB, radius°, centerB]], radius, 0, 360, 360 / LCMdenominator) → cutLCMBVector(centerB, A) → uVector(centerB, B) → vTranslate(circleB, Vector[showfinal * u]) → total0Translate(cutLCMB, Vector[showfinal * u]) → cuttotal0Sequence(CircleSector[centerB, Rotate[AB, (-radius - 360 / denominatorB)°, centerB], Rotate[AB, (-radius)°, centerB]], radius, 0, 360 / denominatorB * numeratorB - 360 / denominatorB, 360 / denominatorB) → ETranslate(shadeB, Vector[showfinal * u]) → FSequence(CircleSector[centerB, Rotate[AB, radius°, centerB], Rotate[AB, (radius + 360 / denominatorR)°, centerB]], radius, 0, 360 / denominatorR * numeratorR - 360 / denominatorR, 360 / denominatorR) → HTranslate(H, Vector[showfinal * u]) → IVector(centerB, J) → wTranslate(circleB, Vector[showfinal * w]) → DTranslate(cutLCMB, Vector[showfinal * w]) → KSequence(CircleSector[centerB, Rotate[AB, radius°, centerB], Rotate[AB, (radius + 360 / LCMdenominator)°, centerB]], radius, (LCMdenominator - LCMnumeratorB) * 360 / LCMdenominator, 360 / LCMdenominator * (M + LCMdenominator - LCMnumeratorB - 1), 360 / LCMdenominator) → NTranslate(N, Vector[showfinal * v]) → OGCD(LCMnumerator, LCMdenominator) → PTranslate(circleB, Vector[showfinal * u]) → CTranslate(cutLCMB, Vector[showfinal * u]) → QSequence(CircleSector[centerB, Rotate[AB, radius°, centerB], Rotate[AB, (radius + 360 / LCMdenominator)°, centerB]], radius, LCMnumeratorB * 360 / LCMdenominator, 360 / LCMdenominator * (LCMnumeratorR - 1), 360 / LCMdenominator) → RTranslate(R, Vector[showfinal * u]) → SSequence(CircleSector[centerB, Rotate[AB, radius°, centerB], Rotate[AB, (radius + 360 / denominatorB)°, centerB]], radius, 0, 360 / denominatorB * numeratorB - 360 / denominatorB, 360 / denominatorB) → TTranslate(circleB, Vector[showfinal * v]) → UTranslate(cutLCMB, Vector[showfinal * v]) → V
AI 绘图提示语参考
画一个由多个同心圆组成的图形,每个圆被等分若干份,并用阴影标出不同部分。圆之间通过平移和重叠显示分数加减法的过程:一个圆的阴影部分与另一个圆的未阴影部分重叠,表示减法;两个圆的阴影部分合并,表示加法。图形中需体现共同分母的概念,用最小公倍数确定等分份数,并用不同颜色区分加法、减法和结果。整体布局清晰,展示分数运算的几何意义,适合数学教学使用。
以上提示语为根据原始绘图命令整理而来,仅供参考。