数列求和一般都要使用简便方法，否则的话会很麻烦。数列求和的简便方法我们归纳了以下几种：

1.公式求和。2.分组求和。3.拆项消去求和。4.错位相减求和。

公式求和主要讲了要记住一些重要的公式，然后套用公式解题，对于公式以记忆为主，不要求理解。

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