Update textbook.fr.md

12.temporary_ins/96.electromagnetism-in-media/20.reflexion-refraction-at-interfaces/10.boundary-conditions/10.main/textbook.fr.md

@@ -47,6 +47,7 @@ $`\overrightarrow{E}_1\,,\overrightarrow{B}_1\,,\overrightarrow{D}_1`$ and $`\ov
 material 1 close to its surface. Likewise an index 2 will be used for
 the fields in the second material.
 
+<br>
 ![](electromag-in-media-reflexion-transmission-fig-31.jpg)   
 _Figure 3.1 : Scheme for deriving boundary conditions for perpendicular field components._
 _$`S_1\,, S_2`$ and $`S'`$ represent respectively the surface at the top, bot- tom and interface._
@@ -54,7 +55,7 @@ _$`S_1\,, S_2`$ and $`S'`$ represent respectively the surface at the top, bot- t
 
 ##### Normal components
 
-__D vector__
+__$`\overrightarrow{D}`$ vector__
 
 Let's apply Maxwell equation (i) to the small cylinder showed in
 figure [3.1] which extends from one side to the other on
@@ -98,7 +99,7 @@ The normal component of the vector $`\overrightarrow{D}`$ is in general disconti
 It is continuos only if there are no conduction charges at the
 separation surface.
 
-__B vector__
+__$`\overrightarrow{B}`$ vector__
 
 The situation is identical for the vector $`\overrightarrow{B}`$, the only difference
 being that the right hand side of the equation is always 0. We
@@ -115,22 +116,23 @@ The normal component of $`\overrightarrow{B}`$ is always conserved.
 
 ##### Tangential components
 
+<br><br>
 ![](electromag-in-media-reflexion-transmission-fig-32.jpg)   
 _Figure 3.2 : Contour for deriving boundary conditions for parallel field components._
 
-__chap5 E vector__
+__$`\overrightarrow{E}`$ vector__
 
 We integrate the third Maxwell equation around the rectangular contour
 C that straddles the boundary of width W and thickness $`\delta`$ as shown in
 figure [3.2.]. We chose to integrate the line integral
 following the right-hand sense relative to the surface normal
-$`\overrightarrow{n_a}`$. By letting $`\delta\right 0`$, we get
+$`\overrightarrow{n_a}`$. By letting $`\delta\rightarrow 0`$, we get
 
 @@@@@@@@@@@
 
 as the line integral along the sides goes to zero and the flux of the
 induction field $`\overrightarrow{B}`$, which is a finite quantity, approaches 0.
-Considering that $`\overrightarrow{CD}-\overrightarrow{AB}=d\overrightarrow{l}`$, we get:
+Considering that $`\overrightarrow{CD}-\overrightarrow{AB}=d\vec{l}`$, we get:
 
 @@@@@@@@@@