Update cheatsheet.fr.md

12.temporary_ins/08.conservative-vector-fields/20.conservative-vector-fields-properties/20.overview/cheatsheet.fr.md

@@ -449,7 +449,7 @@ $`\begin{align}
 &=m\,\left(\dfrac{1}{2}\,\dfrac{d\big(\overrightarrow{\mathscr{v}}\cdot\overrightarrow{\mathscr{v}}\big)}{dt}\,dt\\
 &=m\,\left(\dfrac{1}{2}\,\dfrac{d\,\mathscr{v}^2}{dt}\,dt\\
 &=d\left(\dfrac{m\,\mathscr{v}^2}{2}\right)\\
-\end{array}`$
+\end{align}`$
 
 $`\overrightarrow{F}\cdot\overrightarrow{dl}=\left(m\,\dfrac{d\overrightarrow{\mathscr{v}}}{dt}\right)\cdot\big(\overrightarrow{\mathscr{v}}\,dt\big)`$