In this paper,the author obtains some features of Bertrand curves such as that necessary and sufficient conditions for a Bertrand curve is curve,discusses the distance from a point of a Bertrand curve to the corresponding point of the mate of Γ,the angle of the two tangent lines and so on.

討論了Bertrand曲線的特征www..com五月激情，得出了諸如曲線是Bertrand曲線的充要條件91福利免费视频，Bertrand曲線Γ上的點與其偶線上對應點的距離，以及兩點切線交角等結論高清无码黄在线。

Discusses algebraically and geometrically the properties of the ruled surfaces in the Euclidean three-space, especially, the principal normal surfaces on which there are some special curves, such as Mannheim curves, Bertrand curves and general helices.

在三維歐氏空間中国产精选白浆视频一区二区，作為特殊曲線，Mannheim曲線AAA搡老熟女国产、Bertrand曲線以及一般螺線具有良好的幾何和代數(shù)性質首页国内自拍偷拍视频。討論了三維歐氏空間中特殊曲線的主法線曲面。

bertrand curves：柏特龍曲線

bernstein polynomial 伯思斯坦多項式 | bertrand curves 柏特龍曲線 | bertrand paradox 柏特龍悖論