论文部分内容阅读
运动变化问题是初中数学中的常见问题,此类问题灵活性较强,涉及的知识面较广,对思维能力要求较高,是同学们学习中的一个难点,对于圆中运动变化问题,很多同学经常感到无从下手.其实,处理此类题目,只要掌握如下三个步骤,便可迎刃而解:1.明确题目中运动的对象,按照题目要求作出运动过程中某一时刻的图像;2.寻找题目中隐含的定量、变量和不变的关系,这也是解决这类问题的关键;3.根据已学的知识证明最值位置的存在性及合理性.下面笔者就通过三道圆中的例题进行说明.例1已知:如图1,圆心A(5,0),⊙A的半径为2,与x
The problem of change in movement is a common problem in junior high school mathematics. Such problems are more flexible, involving a wider range of knowledge and higher requirements on thinking ability, which is a difficult point for their students to study. In fact, to deal with such topics, as long as the mastery of the following three steps, you can easily solve: 1 clear the subject of exercise in the subject, in accordance with the requirements of the subject at some point during the movement of the image; 2 to find the problem The implication of quantitative, variable and constant relationship, which is also the key to solve such problems; 3 according to the learned knowledge to prove the existence and rationality of the most value position.The following author through the three circles in the example Example 1 is known: Figure 1, the center A (5,0), ⊙ A radius of 2, and x