关于罗氏平行线一个性质定理的简化证明

A Simplified Proof for a Natural Theorem of Parallel Line

在罗氏几何中 ,仅根据罗氏平行线定义 ,简化证明了定理“在两条平行线之一上的点沿平行方向移动时 ,它到另一平行线的距离单调变小 。

In geometry,based only on the definition of parallel line, the paper proves simply the theorem that ″When a point moves along the paralleled direction on one of the two paralleled lines, the distance monotone of this point to the opposite line decreases with the zero as the ultimate limit″.