在廖老师的上一讲《公式求和》之后，就是本讲《分组求和》的内容。分组求和是指把数列中的某些数通过整理，变为有规律的一组一组的数，从而快速简便地求出结果。分组求和，重在分组这一步，通过分组后，应该有利于下一步的简便计算。

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