The application of Expansion and contraction method in college entrance examination
巧用放缩，解高考题

摘要

放缩法是高中数学中重要而又较难的一种方法，在高考导数压轴题中经常遇到，尤其是与不等式相结合的综合类题目，恰当的放缩会给解题带来意想不到的惊喜，同时放缩也是一种重要的数学思想。新高考重视数学核心素养的考查，而放缩法承载的是推理论证能力，属于逻辑推理的核心素养[1]，这使得其成为命题的热点之一，备受关注。本文研究2023年高考数学试题，发现导数类试题简洁明快，入手容易，但做起来难，不仅仅考查基础知识、基本方法和思想，同时也突出了创新性和理性思维，并且题目的转折点基本在放缩法，下面将详细说明放缩法在高考题中总能起到承上启下、至关重要的作用。

Abstract

Expansion and contraction method is an important and difficult method in high school mathematics. It is often encountered in the derivative closing questions of college entrance examination, especially the comprehensive questions combined with inequalities. Proper shrinkage method will bring unexpected surprises to the solution of the problem, and shrinkage method is also an important mathematical idea. The new college entrance examination attaches great importance to the examination of the core quality of mathematics, while the reduction method bears the ability of reasoning and argumentation, which belongs to the core quality of logical reasoning [1], which makes it become one of the hot topics of proposition and attracts much attention. This paper studies the 2023 college entrance examination mathematics questions, found that derivative questions concise and bright, easy to start, but difficult to do, not only to examine the basic knowledge, basic methods and ideas, but also highlight the innovative and rational thinking, and the turning point of the topic is basically in the reduction method, the following will be detailed to explain the reduction method in the college entrance examination questions can always play a vital role in linking the preceding and the following.