不等式恒成立求参数的取值范围的试题的一般形式是:(其它形式可以仿照):当x≥x_0时,不等式g(x)=f(x,a)≥0恒成立,求实数a的取值范围.关于恒成立的问题,在平时的训练题中经常出现,老师都是作为重点和难点来对待的,解法主要有两种:一是直接求函数g(x)=f(x,a)的最值;二是把参数a分离出来,得到a≥h(x)或a≤h(x)的形式,然后再求函数h(x)的最值.对于方法一,通常需要分类讨论求函数的最值,对学生的能力要求非常高;对于方法二,函数h(x)的形式往往很复杂,求其最值非常困难,况且 Inequality constant Forming the range of parameters seeking the general form of questions is: (other forms can be modeled): When x ≥ x_0, the inequality g (x) = f (x, a) ≥ 0 constant holds, the real a The range of values.As for the problem of constant establishment, often appear in the usual training questions, teachers are treated as the focus and difficulty, there are two main solutions: First, the direct function g (x) = f (x, a), the other is to separate the parameter a and get the form of a≥h (x) or a≤h (x), and then find the value of the function h (x). For method 1, it is usually necessary to classify Discussion of seeking the most value of the function, the ability of students is very demanding; For the second method, the form of the function h (x) is often very complicated, it is very difficult to find the best value Moreover,