解题是由已知说明未知、由题设逐步推理到结论的过程.在这个转化或化归的过程中,思想方法虽然很多,但“构造法”的应用却占有很大的比重.构造法就是依据问题的题设和结论的特点,选择某种数学模型,比如实数、方程(组)、不等式(组)、函数、三角函数、图形、添线等,把问题中的题设和结论之间的关系直接或间接的包含在其中,再应用概念、公式、定理、图形等知识,对这些模型进行处理,把已知到结论的过程有理有据的展现出来.本文以近年 Problem solving is known from the unknown, step by step from the hypothesis to the conclusion of the process.In this process of conversion or return, although there are many ways of thinking, but “construction method ” but the application of a large proportion. Construction method is to choose a mathematical model, such as real number, equation (group), inequality (group), function, trigonometric function, graph, line adding, etc. according to the character of the problem and the conclusion. The conclusion is directly or indirectly involved in the relationship between them, and then apply the concepts, formulas, theorems, graphics and other knowledge, to deal with these models, known to the conclusion of the process of rational and evidence of this article.In recent years