美国著名数学家G·波利亚曾说:“一种想法使用一次是一个技巧,经过多次使用就可成为一种方法.”逼近——是一种基本且重要的解题思想.伴随逼近思想并由此而产生的数学解题方法称之为逼近法.利用不等式的性质、整数的性质、判别式、方程整数根的讨论等是逼近法的主要手段.近几年来,在各级各类初中数学竞赛中.经常遇到用逼近法求解数学题.这类题综合性强、方法独到,常使分析问题能力较弱的初中学生望而却步.但与常规方法比较,逼近法显得思路更深刻、思维更巧妙、过程更简捷,而且还可以启迪智慧,培养学生敏锐的观察力和丰富的想象力.本文试举几例,谈谈用逼近法解题的策略. The famous American mathematician G. Polya once said: “It is a skill to use one idea at a time, and it can be a method after many uses.” Approximation is a basic and important problem-solving idea. Accompanied by approximation. The method of mathematical problem solving that results from thinking and resulting from this is called approximation. Using the nature of inequalities, the nature of integers, discriminants, and the discussion of the integer roots of equations are the main approaches to the approach. In recent years, at various levels In mathematics competitions of junior middle schools, it is often encountered to solve mathematics problems with the approximation method. Such problems are comprehensive and unique methods, often discourage junior high school students with weak problem analysis ability. But compared with conventional methods, the approach method is more profound , Thinking more clever, more simple process, but also can inspire wisdom, training students keen observation and rich imagination. This article gives a few cases, talk about using the approximation method to solve problems.