直线与圆有关的综合问题是高考常见的考查内容之一,主要在圆与直线、向量,圆与轨迹等知识交汇处命制试题,涉及范围、面积、长度等基本量来考查学生对于数形结合、转化化归能力的熟练运用程度,相对较难的直线与圆的综合问题一般需要转化化归思想进行突破,才能使问题的化解事半功倍,解法自然简洁漂亮.本文从直线与圆的“范围问题”、“最值问题”、“相交问题”三类问题入手,通过典型例子分别借助于三个不同的化归思想方法进行转化突破,使问题的破解达到柳暗花明的 The straight line and the circle related comprehensive question is one of the common examinations of the college entrance examination, mainly in the circle and the line, the vector, the circle and the track and so on knowledge interchange test question, involves the scope, the area, the length and so on basic quantity examines the student Combined with the degree of proficiency in conversion into ability, the relatively difficult combination of straight lines and circles generally need to transform into thought to make a breakthrough, in order to make the problem resolved more efficiently, the solution naturally simple and beautiful.This paper from the straight line and circle We will start with three kinds of questions, such as “range problem ”, “most value problem ” and “intersecting problem ”. Through the typical examples, we will make breakthroughs through the transformation of three different methods