There are many difficulties in junior middle school mathematics, but quadratic function, symmetry axis, maximum, discriminant and Vieta theorem are all difficult knowledge points. Circle is also the key point, but with the trend of mathematics in the senior high school entrance examination in recent years, the difficulty of circle is gradually decreasing. Trigonometric functions are also difficult, but not particularly difficult.

In addition, the key and difficult points of junior high school mathematics include: functions (linear function, inverse proportional function and quadratic function) account for about 15% of the total score. Quadratic function, in particular, is the focus and difficulty of the senior high school entrance examination, which involves filling in the blanks and solving problems.