函数中的“任意性”和“存在性”问题,是一种常见的题型,也是高考的热点之一.它们既有区别又有联系,它们的意义和转化方法是不同的,容易混淆.对于函数中的“任意性”和“存在性”问题,我们利用函数与导数的相关知识,可以把相等关系转化 The “” and “existential ” questions in the function are a common type of question and one of the hottest points in the entrance examinations. They are different and related, and their meaning and transformation method are different , Easy to confuse.For the function of “arbitrary ” and “existence ” problem, we use the relevant knowledge of functions and derivatives, you can transform the equal relationship