“三根”是指分式方程的有根、无根(无解)和增根.利用分式方程的“三根”情况,确定分式方程的系数,不仅是近年中考的热点题型,也是学生的难点和棘手的问题.因此,本文通过对近两年的中考题的筛选,选择出了下列最有代表性的三例,进行解答和剖析,目的是使读者对这部分问题做到胸中有数. “Three ” refers to the root of the fractional equation, no root (no solution) and increased root.Using the “three ” case of fractional equation to determine the fractional equation coefficient, not only in recent years the hot test Type, is also a difficult and difficult problem for students.Therefore, this article through the screening of the two years of the senior high school entrance examination questions, select the following three most representative of the three cases, to answer and analysis, the purpose is to make readers on this part of the problem Do what you know.