[1NX] Let \(I,Jβ {\mathbb {R}}\) be intervals. Let \(πΎ:Iβ{\mathbb {R}}^ n\) and \(πΏ:Jβ{\mathbb {R}}^ n\) be two regular curves. We will write \(πΎβπΏ\) if there is a diffeomorphism 1 \(π:Iβ J\) monotonic increasing, such that \(πΎ=πΏβ¦π\).