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问题: 对数比大小

已知1<x<d,a=(以d为底x的对数)^2 b=以d为底x^2的对数 c=以d为底√a的对数 比较大小

解答:

已知:1<x<d,a=logd²_x,b=logd_x²,c=logd_√a, 比较大小

1<x<d--->0=logd_1<logd_x<logd_d=1
a = logd²_x = (logd_x)²>0
b = logd_x² = 2logd_x<(logd_x)(logd_x) = a
c = logd_√a = logd_(logd_x)<0

--->c<a<b