圆是完美的图形。圆既是轴对称图形又是中心对称图形,因而有关圆的问题常常出现一些有多解情形的试题。这一类题目主要是考查分类思想的,解答这类题目的一般思路是:遇到涉及位置关系的要用分类的思想方法,分类时要抓住题目中的不确定因素,选择恰当的分类标准,从而保证准确而迅速地解题。一、点与圆的位置关系 Circle is the perfect figure. Circle is both axisymmetric and centrosymmetric graphics, so the problem of the circle often appear some problems with multiple solutions. This type of topic is mainly to examine the classification of ideas, the general idea of ​​answering such questions are: encountered in relation to the position of the use of classification methods of thought, classification should seize the subject of the uncertainties, select the appropriate classification criteria , So as to ensure accurate and prompt solution to problems. First, the point and the location of the circle