ula_14在formula_15点处的泰勒展开式，考虑到上述极值必要条件，有设formula_94，formula_95，formula_96，则或若formula_14在formula_15点处取得极小值，则要求在formula_15某一邻域内一切点formula_68都必须满足即要求亦即要求formula_105，formula_106即<br>formula_107<br>formula_108此条件反映了formula_14在formula_15点处的黑塞矩阵form