.已知a>1,m>n>0,比较A=a^m+1/a^m和B=a^n+1/a^n的大小
问题描述：
.已知a>1,m>n>0,比较A=a^m+1/a^m和B=a^n+1/a^n的大小
指数,即次方
答
A=a^m+1/a^m=(a^2m+1)/a^mB=a^n+1/a^n=(a^2n+1)/a^nA-B=(a^2m+1)/a^m-(a^2n+1)/a^n=(a^2m*a^n+a^n-a^2n*a^m-a^m)/a^m*a^n分母大于0看分子a^2m*a^n+a^n-a^2n*a^m-a^m=a^m*a^n(a^m-a^n)-(a^m-a^n)=(a^m-a^n)(a^m*a^n-1...