圆周角与圆心角问题是圆的重要内容之一,学生在学习时经常遇到困难,下面就学生在解题中出现的错误分析如下.一、概念不清例1如图1所示,在△ABC中,∠A=70。☉O截△ABC的三边所得弦长相等,则∠BOC的度数为 Circumference angle and the angle of the central angle is an important part of the circle, the students often encounter difficulties in learning, the following students in the problem-solving error analysis is as follows: First, the concept is not clear Example 1 As shown in Figure 1, △ ABC, ∠ A = 70. ☉ O cut △ ABC three sides of the resulting chord equal, then ∠ BOC degrees