1969 AMC 12 第 25 题
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所有题目均经美国数学协会（MAA）官方合法授权使用。
25.
已知 ，则 的最小可能值为：
If it is known that then the least value that can be taken on by is:
以上都不是
none of these
答案：D
小提示：
合并对数，估计 的范围
Combine the logarithms to bound
大提示：
应用
Apply
解答：
对数条件给出 ，所以 。由算术平均值与几何平均值不等式， 当 时取等号。
所以正确答案是 D。
The logarithm condition gives so By AM-GM, Equality is attained at
Therefore, the correct answer is D.
其他年份的第 25 题
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