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等差前n项求和公式
更新时间: 2021-02-27 10:01:14  

1、前n项和公式为:Sn=n*a1 n(n-1)d/2或Sn=n(a1 an)/2。

2、等差数列是常见数列的一种,可以用AP表示,如果一个数列从第二项起,每一项与它的前一项的差等于同一个常数,这个数列就叫做等差数列,而这个常数叫做等差数列的公差,公差常用字母d表示。

关键词: 等差 求和 公式

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