As a geometric figure with axial symmetry and central symmetry, the circle has its special properties and specific solutions. It is the content that high school needs to master. Circle often appears in college entrance examination questions, and it is also a frequent visitor in quality inspection questions around the country.
The "China College Entrance Examination Evaluation System" puts forward an evaluation system with one core, four layers and four wings, in which four items are "core value, subject accomplishment, key ability and necessary knowledge", which is a refinement of the quality education goal of the college entrance examination and answers the question of "what to test". Although the Apollonius circle is not clearly put forward in the textbook, only the curve equation has appeared in the textbook exercises, but because the Apollonius circle involves the distance between points on the plane and the nature of the bisector of the triangle angle.