不等式是高中数学的重要内容及求解数学问题的重要工具,运用重要不等式证明问题或解决最值问题时,根据不等式的结构,常常需要合理变形把问题转化为适合使用重要不等式结构的形式.在求最值时还要充分重视运用“一正、二定、三相等”三个条件,而成功实现变形是解决此类问题的关键.下面举例说明常见的方法与技巧.一、拆项 Inequality is an important content of high school mathematics and an important tool for solving mathematical problems. When using important inequalities to prove the problem or solve the problem of the most value, according to the structure of inequality, it is often necessary to transform the problem into a form suitable for using the important inequality structure. At the most value, we must pay full attention to the use of “one positive, two fixed, three-phase, etc.” three conditions, and the successful implementation of deformation is the key to solving such problems. The following examples illustrate common methods and techniques.