数学应用题是指有实际背景或问题有实际意义的数学问题。在解应用题时 ,应突出达到以下要求 :认真读懂与领会题意 ;分清有关数量之间的关系 ,特别是相等或不等关系 ;以简明的方法译出数学关系式并解出结论。显然 ,就应用题型的特征构造出数学模型是解题的关键。1　构造函数例 1 Mathematical application problems refer to mathematical problems with practical background or practical implications. When solving an application problem, the following requirements should be highlighted: to carefully read and comprehend the meaning of the subject; to clarify the relationship between the relevant quantities, especially the equal or inequitable relationship; to use a concise method to translate the mathematical relations and solve the conclusions. Obviously, the key to solving a problem is to construct a mathematical model on the features of the problem type. 1 Constructor Example 1