Update textbook.fr.md

12.temporary_ins/40.classical-mechanics/30.n3/07.coherence/textbook.fr.md

@@ -558,15 +558,15 @@ $`\begin{align}
 ---------------
 
 $`\begin{align}
-\dfrac{d^2\overrightarrow{e_{\theta}}}{dt^2}&=\dfrac{d}{dt}\left(\underbrace{\dfrac{d\overrightarrow{e_{\rho}}}{dt}}_{=\omega\,\vec{e_{\theta}}}\right)\\
+\dfrac{d^2\overrightarrow{e_{\theta}}}{dt^2}&=\dfrac{d}{dt}\Big(\underbrace{\dfrac{d\overrightarrow{e_{\rho}}}{dt}}_{=\omega\,\vec{e_{\theta}}}\Big)\\
 \\
 &=\dfrac{d}{dt}\left(\omega\,\overrightarrow{e_{\theta}}\right)\\
 \\
-&=\dfrac{d\omega}{dt}\;\overrightarrow{e_{\theta}}+\omega\;\dfrac{d\overrightarrow{e_{\theta}}}{dt}\\
+&=\dfrac{d\omega}{dt}\;\overrightarrow{e_{\theta}}\;+\;\omega\;\dfrac{d\overrightarrow{e_{\theta}}}{dt}\\
 \\
-&=\dfrac{d\omega}{dt}\;\overrightarrow{e_{\theta}}+\omega\;\big(-\;\omega\;\overrightarrow{e_{\rho}}\big)\\
+&=\dfrac{d\omega}{dt}\;\overrightarrow{e_{\theta}}\;+\;\omega\;\big(-\,\omega\;\overrightarrow{e_{\rho}}\big)\\
 \\
-&=\dfrac{d\omega}{dt}\;\overrightarrow{e_{\theta}}-\omega^2\;\overrightarrow{e_{\rho}}
+&=\dfrac{d\omega}{dt}\;\overrightarrow{e_{\theta}}\;-\;\omega^2\;\overrightarrow{e_{\rho}}
 \end{align}`$