Update textbook.fr.md

00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/05.classical-mechanics/vector-analysis/textbook.fr.md

@@ -297,8 +297,10 @@ $`\overrightarrow{U}`$ et $`\overrightarrow{V}`$ sont colinéaires
 $`\quad\Longrightarrow\quad ...`$
 
 $`\overrightarrow{U}`$ et $`\overrightarrow{V}`$ sont colinéaires 
-$`\;\Longrightarrow\left|\overrightarrow{U}\cdot\overrightarrow{V}=+||\overrightarrow{U}||\cdot
-||\overrightarrow{V}||\,si\,\widehat{\overrightarrow{U},\overrightarrow{V}}=0 \\ 
+$`\;\Longrightarrow\left|\begin{array}{l}\overrightarrow{U}\cdot\overrightarrow{V}=+||\overrightarrow{U}||\cdot
+||\overrightarrow{V}||\,si\,\widehat{\overrightarrow{U},\overrightarrow{V}}=0 
+\\ \,
+\\
  \overrightarrow{U}\cdot\overrightarrow{V}=-||\overrightarrow{U}||\cdot||\overrightarrow{V}||
  \,si\, \widehat{\overrightarrow{U},\overrightarrow{V}}=\pi\right.`$ 
  
@@ -309,6 +311,7 @@ $`\;\Longrightarrow\left|\overrightarrow{U}\cdot\overrightarrow{V}=+||\overright
 \right.`$ 
 
 $` \underline{\overrightarrow{B}}^{\,0}_{\,ref}=\left|\begin{array}{l} +\,B_{ref}^0\,cos\,\theta_{ref} 
+\\ :,
 \\ +\,B_{ref}^0\,sin\,\theta_{ref} \end{array}\right.\quad , \quad `$ 
 
 $` \underline{\overrightarrow{B}}^{\,0}_{\,trans}=\left|\begin{array}{l} -\,B_{trans}^0\,cos\,\theta_{trans} \\ 0