目前 ,人们对比较变量大小之间关系的不等式较为关注 ,但是 ,笔者发现 ,有一些不等式在变量的定义域内 ,经过变量置换 ,可以得到关于变量个数的一些单调函数 .为了讨论方便 ,设实函数 f(x)的定义域为x∈(a ,b) ,实数Pi0 (1≤i≤n) ,n∈N .记λn=∑ni=1Pi,An=∑ni=1Pixi/λn,Bn At present, people are more concerned about the inequality of the relationship between the size of the comparison variables. However, the author finds that there are some inequalities within the domain of variables, through the replacement of variables, to obtain some monotonic functions on the number of variables. The function f(x) has the domain x∈(a,b), the real number Pi0 (1≤i≤n), and n∈N. Remember λn=∑ni=1Pi,An=∑ni=1Pixi/λn,Bn