diff --git a/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/05.classical-mechanics/vector-analysis/textbook.fr.md b/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/05.classical-mechanics/vector-analysis/textbook.fr.md
index 555040e75..e7fd7d63f 100644
--- a/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/05.classical-mechanics/vector-analysis/textbook.fr.md
+++ b/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/05.classical-mechanics/vector-analysis/textbook.fr.md
@@ -305,6 +305,15 @@ $`\quad\Longleftrightarrow\quad cos(\widehat{\overrightarrow{U},\overrightarrow{
 "$`\overrightarrow{U}`$ et $`\overrightarrow{V}`$ sont colinéaires"
 $`\quad\Longrightarrow\quad ...`$
 
+$` \underline{\overrightarrow{B}}^{\,0}_{\,inc}=\left|\begin{array}{l} -\,B_{inc}^0\,cos\,\theta_{inc} \\ 0 
+\\ +\,B_{inc}^0\,sin\,\theta_{inc} \end{array}\right. \quad , \quad`$ 
+
+$` \underline{\overrightarrow{B}}^{\,0}_{\,ref}=\left|\begin{array}{l} +\,B_{ref}^0\,cos\,\theta_{ref} \\ 0 
+\\ +\,B_{ref}^0\,sin\,\theta_{ref} \end{array}\right.\quad , \quad `$ 
+
+$` \underline{\overrightarrow{B}}^{\,0}_{\,trans}=\left|\begin{array}{l} -\,B_{trans}^0\,cos\,\theta_{trans} \\ 0 
+\\ +\,B_{trans}^0\,sin\,\theta_{trans} \end{array}\right. `$ ,
+
 ##### Producto escalar de dos vectores ortogonales /Produit scalaire de 2 vecteurs orthogonaux /
 
 ##### Caractéristiques des vecteurs de base d’une base orthonormée