二次型理论在多元极值问题上应用的剖析

Analysis for the Application of Qudratic Form Theory to Multipvariable Function Extreme Value

利用线性代数的二次型理论判定多元极值问题，确实比较方便。但是，由于其充分条件对矩阵Ａ的正定或负定要求很严，有相当多的题目不能满足，所以它的应用是有局限的，需要进一步研究。

It is convenienl that the problem about multipvariable extreme value can be confirmed by meams of linear algebric qudratic form theories. However, because its safficienl condition for the positive definiteness or negative definiteness is severe (strict), many cases don't satify it, which leads to the limitation for its applications.