二次函数是高考的重点内容,可以说每年必考。但是学生对它的掌握程度普遍不高。在初中教材中,虽然对二次函数作了较详细的研究,但由于初中学生基础薄弱,又受其接受能力的限制,这部分内容的学 Quadratic function is the key content of the college entrance examination, you can say that the annual test. However, students generally have a low level of mastery over it. In junior high school textbooks, although a more detailed study of the quadratic function, but due to the weak foundation of junior high school students, but also by their ability to accept the limitations of this part of the study