Update cheatsheet.fr.md

12.temporary_ins/20.magnetostatics-vacuum/20.causes-stationary-magnetic-field/20.overview/cheatsheet.fr.md

@@ -587,12 +587,10 @@ de la spire, qui porte l'élément de courant $`I\,\overrightarrow{dl}_{P'}`$
 * L'**ensemble des points $`P`$ de la spire**, de coordonnées $`P = (R,\,\varphi_M,\,0)`$
   s'obtient en faisant varier *$`\varphi_P`$ entre $`0`$ et $`2\pi`$*.   
   <br>
-**$`\mathbf{H_M}`$** $`\displaystyle\;=\,\int_{\varphi=0}^{2\pi} \dfrac{I}{4\pi}\cdot\dfrac{R^2}{(R^2+z_M^2)^{\,3/2}} d\varphi`$   
-  <br>
-$`\hspace{1.7cm}=\dfrac{I}{4\pi}\cdot\dfrac{R^2}{(R^2+z_M^2)^{\,3/2}}\times \int_{\varphi=0}^{2\pi}\,d\varphi`$   
-  <br>
-$`\hspace{1.7cm}=\dfrac{I}{4\pi}\cdot\dfrac{R^2}{(R^2+z_M^2)^{\,3/2}}\times 2\pi`$   
+**$`\mathbf{H_M}`$** *$`\displaystyle\mathbf{\;=\,\int_{\varphi=0}^{2\pi} \dfrac{I}{4\pi}\cdot\dfrac{R^2}{(R^2+z_M^2)^{\,3/2}} d\varphi}`$*   
   <br>
+$`\displaystyle\hspace{1.7cm}=\dfrac{I}{4\pi}\cdot\dfrac{R^2}{(R^2+z_M^2)^{\,3/2}}\;\underbrace{\int_{\varphi = 0}^{2\pi}\,d\varphi}_{\color{blue}{=\big[\varphi\big]_0^{2\pi}=2\pi-0}}`$   
+<br>
 **$`\mathbf{\hspace{1.7cm}=\dfrac{I}{2}\cdot\dfrac{R^2}{(R^2+z_M^2)^{\,3/2}}}`$**,  
   <br>
 Soit