特殊圆形部分的计算练习
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本范例通过3道递进难度的题目,练习特殊圆心角对应的扇形面积、弧长及圆周长的计算。核心数学概念包括:圆心角公式、弧长公式L=nπr/180、扇形面积公式S=nπr²/360、圆的周长公式C=2πr和面积公式A=πr²。作图要点:使用GeoGebra的If条件判断实现答案验证,Random命令随机生成题目参数,Sequence和Element从题库中选取题目,Textfield和Text实现输入框与反馈文本显示,Translate处理文本翻译,Split和IndexOf解析输入内容。本练习适合7-8年级学生,可用于课堂巩固或课后自主练习,培养公式推导与应用能力。
GeoGebra 命令及参数
Join(Sequence[Shuffle[{1, 2}], k, 1, 50]) → CaseQListRandom(1, 3, 100) → CaseLevel1List, {2, 2, 1, 1, 2, 1, 1, 3, 2, 2, 1, 2, 2, 3, 3, 1, 2, 1, 2, 3, 1, 3, 1, 2, 1, 1, 1, 3, 2, 2, 3, 3, 2, 3, 3, 1, 2, 2, 2, 1, 1, 2, 3, 2, 2, 3, 1, 1, 1, 1, 2, 1, 2, 1, 2, 3, 3, 1, 2, 1, 3, 1, 2, 1, 2, 3, 1, 3, 3, 3, 3, 2, 1, 3, 3, 2, 3, 3, 3, 1, 1, 3, 2, 3, 2, 3, 1, 3, 2, 1, 3, 3, 2, 2, 2, 3, 1, 3, 3, 3}Random(1, 5, 100) → CaseLevel2List, {2, 3, 5, 2, 1, 1, 5, 5, 1, 5, 4, 4, 5, 2, 1, 3, 2, 4, 5, 4, 1, 4, 5, 4, 4, 1, 2, 5, 3, 4, 4, 5, 4, 1, 5, 4, 4, 1, 5, 5, 4, 3, 1, 4, 3, 1, 3, 1, 2, 2, 4, 3, 3, 5, 4, 5, 2, 4, 3, 4, 1, 4, 3, 3, 2, 5, 5, 1, 4, 1, 5, 3, 5, 2, 5, 4, 5, 1, 1, 5, 5, 2, 5, 5, 1, 5, 3, 1, 4, 3, 5, 1, 2, 3, 1, 4, 4, 2, 3, 4}Random(1, 8, 100) → CaseLevel3List, {5, 7, 2, 2, 3, 8, 5, 2, 6, 8, 5, 6, 8, 8, 2, 5, 8, 3, 3, 1, 6, 7, 4, 7, 8, 6, 2, 3, 7, 3, 4, 8, 4, 7, 6, 8, 2, 6, 3, 1, 1, 2, 5, 1, 7, 2, 8, 7, 1, 3, 5, 3, 8, 2, 7, 4, 2, 2, 1, 7, 7, 8, 1, 2, 1, 3, 7, 1, 3, 6, 1, 2, 3, 4, 1, 8, 5, 8, 4, 3, 3, 1, 3, 3, 5, 3, 4, 3, 1, 8, 3, 5, 2, 1, 8, 6, 7, 5, 7, 3}If(level ≟ 1, If[CaseLevel1 ≟ 1, 0.5, CaseLevel1 ≟ 2, 0.25, 1 / 8], level ≟ 2, If[CaseLevel2 ≟ 1, 1 / 3, CaseLevel2 ≟ 2, 1 / 6, CaseLevel2 ≟ 3, 1 / 12, CaseLevel2 ≟ 4, 1 / 5, 1 / 10], If[CaseLevel3 ≟ 1, 3 / 4, CaseLevel3 ≟ 2, 3 / 8, CaseLevel3 ≟ 3, 5 / 8, CaseLevel3 ≟ 4, 7 / 8, CaseLevel3 ≟ 5, 2 / 3, CaseLevel3 ≟ 6, 5 / 6, CaseLevel3 ≟ 7, 5 / 9, 7 / 9]) → facIf(CaseQ ≟ 1, ((Radius^(2) * pi) * fac), (((2 * Radius) * pi) * fac) + (2 * Radius)) → solutionSequence(Random[1, 10], i, 1, 10) → randomNumbers, {3, 8, 5, 2, 4, 2, 9, 8, 3, 8}Element(randomNumbers, Mod[questionCount, Length[randomNumbers]] + 1) → randomNumberTextfield(input) → inputBoxJoin({Sequence[Segment[Corner[4] + (pixMat * ((k * stepXY), 0)), Corner[4] + (pixMat * ((k * stepXY), maxY))], k, 0, maxX / stepXY], Sequence[Segment[Corner[4] + (pixMat * (0, (k * stepXY))), Corner[4] + (pixMat * (maxX, (k * stepXY)))], k, 0, maxY / stepXY]}) → RasterJoin({Sequence[Text[UnicodeToLetter[65 + k], Midpoint[Corner[4] + (pixMat * ((k * stepXY), maxY)), Corner[4] + (pixMat * (((k + 1) * stepXY), maxY))], false, true, 0, -1], k, 0, maxX / stepXY - 1], Sequence[Text[("" * k), Midpoint[Corner[4] + (pixMat * (maxX, ((k - 1) * stepXY))), Corner[4] + (pixMat * (maxX, (k * stepXY)))], false, true, 1, 0], k, 1, maxY / stepXY]}) → CapRasterSequence(Sequence[Corner[4] + (pixMat * ((k * stepXY), (m * stepXY))), k, 0, maxX / stepXY], m, 0, maxY / stepXY) → PRIf(CaseQ ≟ 1, "Flächeninhalt A", "Umfang u") → txtQIf(CaseLevel1 ≟ 1, "Halbkreis", CaseLevel1 ≟ 2, "Viertelkreis", "Achtelkreis") → txtLevel1If(CaseLevel2 ≟ 1, "Drittelkreis", CaseLevel2 ≟ 2, "Sechstelkreis", CaseLevel2 ≟ 3, "Zwölftelkreis", CaseLevel2 ≟ 4, "Fünftelkreis", "Zehntelkreis") → txtLevel2If(CaseLevel3 ≟ 1, "\dfrac{3}{4}\:-Kreis", CaseLevel3 ≟ 6, "\dfrac{5}{6}\:-Kreis", CaseLevel3 ≟ 7, "\dfrac{5}{9}\:-Kreis", "\dfrac{7}{9}\:-Kreis", CaseLevel3 ≟ 2, "\dfrac{3}{8}\:-Kreis", CaseLevel3 ≟ 3, "\dfrac{5}{8}\:-Kreis", CaseLevel3 ≟ 4, "\dfrac{7}{8}\:-Kreis", CaseLevel3 ≟ 5, "\dfrac{2}{3}\:-Kreis") → txtLevel3Split(Text[(round(solution, 2) * "")], {""}) → ListSolValueIf(Defined[IndexOf[".", ListSolValue]], Length[ListSolValue] - IndexOf[".", ListSolValue], 0) → numberCommaSolutionNumerator(fac) → numFacDenominator(fac) → denFacTranslate(imgChilliRot1, Vector[((0.8 * dimChilli), 0)]) → imgChilliRot2Translate(imgChilliRot1, Vector[(2 * Vector[((0.8 * dimChilli), 0)])]) → imgChilliRot3Translate(imgChilliGrau1, Vector[(1 * Vector[((0.8 * dimChilli), 0)])]) → imgChilliGrau2Text((("\textsf{" * If[CaseQ ≟ 1, "cm²\vphantom{cm²}", "cm\vphantom{cm²}"]) * "}"), PosIB + (2.35, -0.225), false, true, 1, 0) → txtUnitIf(CaseQ ≟ 1, (Radius^(2) * pi), ((2 * Radius) * pi)) → wholeCircleIf(CaseQ ≟ 2, ((Radius^(2) * pi) * fac), (((2 * Radius) * pi) * fac) + (2 * Radius)) → wrongSolutionSplit(Text[(input * "")], {""}) → ListInputValueIf(Defined[IndexOf[".", ListInputValue]], Length[ListInputValue] - IndexOf[".", ListInputValue], 0) → numberCommaInputSplit(Text[(round(solution, numberCommaInput) * "")], {""}) → ListSolRoundInputSplit(Text[(round(solution, 10) * "")], {""}) → ListSolWholeIndexOf(".", ListInputValue) → indexCommaInputIndexOf(".", ListSolWhole) → indexCommaSolution