构造法是运用数学的基本思想原理,经过认真观察,深入思考,构造出问题的数学模型,从而使问题得以解决.构造的内涵相当丰富,没有固定的模式可以套用,它以广泛抽象的普遍性与现实问题的特殊性为基础,针对具体问题的特点,采用相应的解决问题的方法.数学中的所谓构造法是通过观察、联想, Constructive method is the use of mathematical basic ideological principle, after careful observation, in-depth thinking, to construct the mathematical model of the problem, so that the problem can be solved.The connotation of the structure is quite rich, there is no fixed pattern can be applied, it is widespread abstract universality And the particularity of the reality problem, based on the characteristics of the specific problem, the corresponding problem-solving method is adopted.The so-called construction method in mathematics is through observation, association,