1956 AMC 12 第 18 题
先试着解答 1956 AMC 12 第 18 题，然后核对你的答案与精心整理的解答，解答来自 LIVE by Po-Shen Loh。你也可以参加完整限时模拟考试、查看全部 1956 AMC 12 解答，或核对答案。
所有题目均经美国数学协会（MAA）官方合法授权使用。
18.
若 ，则 等于：
If then equals:
答案：E
小提示：
将 写成
Write as
大提示：
为正数
The quantity is positive
解答：
我们有 由于 为正数，所以 。取倒数得 。
因此，正确答案是 E。
We have Since is positive, Taking the reciprocal gives
Thus, the correct answer is E.
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