与圆有关的最值问题主要体现为直线与圆的位置关系中,解决此类问题数形结合是首选方法,因此解题时注意观察所给式子的几何意义,充分利 The problem of the most value related to the circle is mainly reflected in the positional relationship between the straight line and the circle. Solving the combination of numbers and shapes of this type of problem is the preferred method. Therefore, when solving a problem, pay attention to the geometric meaning of the given formula and make full use of it.