大家都知道,判别式主要应用于判断一元二次方程根的情况,这类问题比较简单,下面介绍判别式其他方面的一些应用·一、求条件最值问题例1已知实数x,y满足x2-12y=0,求x-3y的最值·分析:运用设“k”法消去y,即可整理成x的一元二次方程·解:设x-3y=k,则y=x3-k,代入x2-12y=0,化简得x2 As we all know, the discriminant equation is mainly used to determine the condition of the root of a quadratic equation. This type of problem is relatively simple. The following describes some applications of other aspects of the discriminant. First, find the condition of the maximum value. Example 1 Known real number x,y is satisfied X2-12y=0, find x-3y the most value analysis: use the “k” method to eliminate y, can be arranged into x one-dimensional quadratic equation solution: Let x-3y = k, then y = x3- k, substitute x2-12y=0, simplify x2