不等式是中学数学的基础和重要部分 ,是历年高考考查的重点内容 .在不等式的教学内容中 ,不等式的证明是难点 .本文介绍用解析几何方法证明不等式的几种途径 .读者从中可体会到用解析方法证明不等式 ,思路清新 ,直观明快 .一、利用距离例 1　已知正数a、b满足a +b=1.求证 :(a+2 Inequality is the basic and important part of middle school mathematics, and it is the key content of the college entrance examination. In the teaching content of inequality, the proof of inequality is difficult. This paper introduces several ways to prove the inequality with analytical geometry. The reader can experience it. Analytical methods prove inequality, fresh ideas, intuitive and bright. First, the use of distance example 1 Known positive numbers a, b meet a + b = 1. Proof: (a + 2