Update cheatsheet.fr.md

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

@@ -424,11 +424,15 @@ Par ailleurs,$`\phi`$ étant un champ scalaire, sa différentielle exprimée en
 $`\mathbf{d\phi=\left.\dfrac{\partial \phi}{\partial \alpha}\right|_M\cdot dl_{\alpha} + \left.\dfrac{\partial \phi}{\partial \beta}\right|_M\cdot dl_{\beta} + \left.\dfrac{\partial \phi}{\partial \gamma}\right|_M\cdot dl_{\gamma}}`$
 --------------------->
 
-$`\mathbf{d\phi}=\dfrac{\partial \phi}{\partial \alpha}\cdot d\alpha + \dfrac{\partial \phi}{\partial \beta}\cdot d\beta + \dfrac{\partial \phi}{\partial \gamma}\cdot d\gamma`$
+*$`\mathbf{d\phi}`$*$`\;=\dfrac{\partial \phi}{\partial \alpha}\cdot d\alpha + \dfrac{\partial \phi}{\partial \beta}\cdot d\beta + \dfrac{\partial \phi}{\partial \gamma}\cdot d\gamma`$
 
 $`\mathbf{d\phi}=
-\dfrac{\partial \phi}{\partial dl_{\alpha}}\,\dfrac{\partial dl_{\alpha}}{\partial \alpha}\, d\alpha}
-+\dfrac{\partial \phi}{\partial dl_{\beta}}\,\dfrac{\partial dl_{\beta}}{\partial \beta}\, d\beta}
+\dfrac{\partial \phi}{\partial dl_{\alpha}}\,\dfrac{\partial dl_{\alpha}}{\partial \alpha}\, d\alpha}`$
+$`+\dfrac{\partial \phi}{\partial dl_{\beta}}\,\dfrac{\partial dl_{\beta}}{\partial \beta}\, d\beta}
++\dfrac{\partial \phi}{\partial dl_{\gamma}}\,\dfrac{\partial dl_{\gamma}}{\partial \gamma}\, d\gamma}`$
+
+$`\mathbf{d\phi}=\dfrac{\partial \phi}{\partial dl_{\alpha}}\,\dfrac{\partial dl_{\alpha}}{\partial \alpha}\, d\alpha}`$
+$`+\dfrac{\partial \phi}{\partial dl_{\beta}}\,\dfrac{\partial dl_{\beta}}{\partial \beta}\, d\beta}
 +\dfrac{\partial \phi}{\partial dl_{\gamma}}\,\dfrac{\partial dl_{\gamma}}{\partial \gamma}\, d\gamma}`$