极端值法是运用极限思想,得出极大(小)值,然后对极值区间根据化学原理进行分析、推理作出结论的方法,通常把可逆反应假设为完全反应,把多个反应假设为单一反应,把混合物假设为纯净物(或少一成分的混合物).它是指导平均值法、十字交叉法和不等式解题的重要 The extreme value method is the method of using the limit idea to derive the maximum (small) value, and then makes conclusions based on analysis and inference of the extreme value range according to the chemical principle. Usually, the reversible reaction is assumed to be a complete response, and the multiple reactions are assumed to be single. The reaction, the mixture is assumed to be pure (or a mixture of less than one component). It is important to guide the mean, crisscross, and inequality problems.