含绝对值的不等式的证明是学习的难点,很多学生对此类问题因苦于找不到解题思路而望题兴叹.本文以近几年的模拟题为例,试图揭示其证明的策略.一、配凑常数此法先通过取特殊值,配凑常数,消去参变量,再运用绝对值不等式进行放缩.例1已知函数f(x)=x2+ax+b(a、b∈R)的定义域为[-1,1 The proof of the inequality with absolute value is the difficulty of learning. Many students are sighing at the problem because they can’t find the problem-solving ideas. This paper uses the simulation questions in recent years as an example to try to reveal its proof strategy. Matching constants This method first eliminates the arguments by taking special values ​​and matching constants, and then scales them using absolute value inequalities. Example 1 Known function f(x)=x2+ax+b (a, b∈R) The definition of the domain is [-1, 1