不等式的证明方法灵活多样,从技巧角度看有放缩法,换元法;从思路探究角度看有分析法,综合法,比较法;从思想方法角度看有数形结合(构造图形),函数思想(构造函数)等等.由于不等式问题可以理解为函数(一元或多元)的某个变量范围问题,从这个角度看不等式的本质是函数问题,所以从广义上讲,所有的不等式都可以用函数的思想加以研究.再则高中数学引入导数这一工具后,函数思想在不等式问题中更是如虎添翼.但是,由于不等式的形式多样,处理灵活,如何转化为合 Inequality is flexible and diverse, and there are methods of scaling and changing from the perspective of technique. There are analytic, synthetical, and comparative methods from the perspective of thinking. There are several forms of conjunctive (structural graph), functional thinking (Constructor), etc. Since the problem of inequality can be understood as a range of variables in a function (unary or multivariate), the essence of inequality is a matter of function from this point of view, so in a broad sense all inequalities can be represented by functions The idea of ​​function is even more powerful in the problem of inequality.But due to the variety of inequalities, flexible handling, how to convert into