一元二次方程历来是中考命题的热点 ,而一些需分类求解的一元二次方程又极易让同学们失分 .故本文选取几例加以剖析 ,以期引起同学们的重视 .一、对二次项系数需分类求解例 1　若关于ｘ的方程 (1-ｍ2 )ｘ2 +2ｍｘ -1=0的所有根都是比 1小的正实数 ,则实数ｍ的取值范围是 .分析 The one-membered quadratic equation has always been the hot topic of the examination proposition, and some unary quadratic equations that need to be classified and solved make it easy for the students to lose points. Therefore, this article selects several cases for analysis in order to arouse the attention of the students. Item coefficients need to be classified Solution Example 1 If all roots of equation (1-m2) x2 +2mx -1=0 for x are positive real numbers smaller than 1, then the range of the real number m is.