摘要:
本文讨论了两个不同正实数x和y的对数平均L(x,y)=(x-y)/(logx-logy)与双参数广义Muirhead平均M(a,b;x,y)=[(xayb+ xbya)/2]1/(a+b)之间的比较,得到了如下三个结论:(1)若(a,b)∈D1 ∪E1 ∪L0,则M(a,b;x,y)<L(x,y);(2)若(a,b)∈D2 ∪E2,则M(a,b;x,们>L(x,们;(3)若(a,b)∈D3 ∪E3,则存在x1,y1,x2,y2,使得M(a,b;x1,y1)<L(xl,y1)和M(a,b;x2,y2)>L(x2,y2).其中D1={(a,b)∈R2:a+b≠0,b>a,ω1(a,b)≤0,ω2 (a,b)≤0},E1={(a,b)∈R2:a+b≠0,b<a,ω1(a,b)≤0,ω2 (a,b)≤0},D2={(a,b)∈R2:ab≤0,b>a,ω1(a,b)≥0},E2={(a,b)∈R2:ab≤0,b<a,ω1(a,b)≥0},D3={(a,b)∈R2:b>a>0,ω1(a,b)>0}∪{(a,b)∈R2:b>a>0,ω1(a,b)=0,ω2(a,b)>0}∪{(a,b)∈R2:b>a,ab≤0,ω1(a,b)<0,ω2(a,b)>0},E3={(a,b)∈R2:a>b>0,ω1(a,b)>0}∪{(a,b)∈R2:a>b>0,ω1(a,b)=0,ω2(a,b)>0}∪{(a,b)∈R2:a>b,ab≤0,ω1(a,b)<0,ω2(a,b)>0},L0={(a,b)∈R2:a=b≠0},ω1(a,b)=(a+b)[3(a-b)2-(a+b)],ω2(a,b)=(a+b)[2(a-b)2+1]-3(a2+ b2).