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发帖数: 2632 | 1 ☆─────────────────────────────────────☆
destro (the forgiving) 于 (Tue May 25 15:35:10 2004) 提到:
从现在开始，从友谊出发，我把本节目的TITLE 换成“destro爱CS”。
昨天那题其实分两部分，我给的只是第一部分。现在把第二部分也给出，因为这样可能可
以解释有人的问题，让大家看到某些证法是不正确的。
Let $A$ and $B$ be two points on a plane, and the line segment joining $A$
and $B$ has length 1. Prove, for any positive number $a$ that is NOT
an integer and any continuous curve joining $A$ and $B$, there do
not exist two points $X$ and $Y$ on the curve such that segment $XY$ is
parallel to |
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