提取公因式法是因式分解最基本最重要的方法之一．在学习时，请同学们注意以下几个问题．一、理解提取公因式法的依据提取公因式是乘法分配律的逆用．分配律ｍ（a＋ｂ＋ｃ）ｍa＋ｍｂ＋ｍc．提公因式二、必须提取最大的公因式例１把４ａ～３ｂ－６ａ～２b～２＋２ａ～２ｂ分解 The extraction of the common factor method is one of the most basic and most important methods of factorization. When studying, ask the students to pay attention to the following questions. First, to understand the basis for the extraction of the common factor method The extraction of the common factor is the inverse of the law of multiplicative distribution. Distribution law m(a+b+c)ma+mb+mc. The public factor II must be extracted and the largest common factor must be extracted. Example 1 Decomposition of 4a~3b-6a~2b~2+2a~2b