等差数列通项公式与前n项和公式交互演示
2020-03-11 12:00
本GeoGebra范例动态演示等差数列的核心公式：通项公式 aₙ = a₁ + (n-1)d 与前n项和公式 Sₙ = na₁ + n(n-1)d/2。通过滑块控件可实时调节首项 a₁、公差 d 和项数 n，观察数列各项的变化及求和结果。利用Sequence命令生成数列项，结合Vector与Point将数列可视化呈现，Text对象标注关键公式与数值。适合高中数学数列章节教学，帮助学生直观理解等差数列的递推关系与求和规律。
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中职数学GeoGebra互动教学资源库
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