摘要
本文按照R~3经典微分几何的研究思路,对R~n中的正则曲线作了初步探讨,我们首先从R~n中正则曲线的定义入手,然后介绍了正则曲线的自然参数表示和Frenet-Serret公式,接下来利用这一重要公式给出了R~n中正则曲线的各阶曲率的计算公式,讨论了R~n中的一般螺旋线和曲线的平坦性,我们还对R~n中的闭曲线证明了一个几何不等式。
In this thesis,following the ideas of classical differential geometry in R~3,we discuss regular curves in R~n.From the beginning of definition of regular curves,we introduce the natural para-metrization and Frenet-Serret Formula of regular curves.Then,by the Formula,we give calculation formulas of regular curves' curvatures ,and discuss the general helices and flatness of curves in R~n,finally we prove a geometry inequality of curvatures and arc length.
引文
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