两例综合题都以旋转为背景,其中压轴问的解答均要先确定满足条件的点P的位置,再根据旋转该点轨迹为圆弧的特征,引入辅助圆,以直线与圆相切的这种特殊性为切入点,这样的思考具有直观、形象、简捷的优点. The two comprehensive questions are all based on the rotation. In the solution of the axis of pressure, the position of the point P that satisfies the condition must be determined first. Then according to the feature that the trajectory of the point is circular, the auxiliary circle is introduced to make the line tangent to the circle This particularity as a starting point, such thinking has the advantages of intuitive, vivid, simple.