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圆的切线是九年级数学中的一个重要内容,是在中考中常考的一个知识点。而相当一部分学生在证明一条直线是圆的切线时,有的无从下手,有的证明过程不完整。下面就圆的切线证明归纳总结如下:一、掌握切线的判定方法,理解切线的概念与特征1.根据定义,即和圆只有一个公共点的直线是圆的切线。2.到圆心的距离等于半径的直线是圆的切线。
Round tangent is an important content in the ninth grade mathematics, is a knowledge point in the exam. While a considerable number of students prove a straight line is a tangent, some can not start, and some prove that the process is incomplete. The following is a summary of the tangent of the circle summarized as follows: First, grasp the tangent decision method to understand the concept and characteristics of the tangent 1. According to the definition, that is, only one point and the circle is a straight line tangent. 2. The distance from the center of the circle equal to the radius is tangent to the circle.