Update cheatsheet.fr.md

12.temporary_ins/40.classical-mechanics/30.n3/40.point-dynamics/20.overview/cheatsheet.fr.md

@@ -243,7 +243,7 @@ $`\hspace{0.5cm}=\dfrac{d\big(m\overrightarrow{v}\big)}{dt}`$
 <br>
 **$`\Large\mathbf{
 \hspace{0.5cm}=m\,\overrightarrow{a}\;+\underbrace{\dfrac{dm}{dt}\cdot\overrightarrow{v}}
-_{\color{blue}{\text{  si masse}\\ \text{non constante}}}}`$**
+_{\color{blue}{\large\;\;\;\;\text{si masse}\\ \text{non constante}}}}`$**
 
 
 <!----------------------