From 3f2e8de4e215b44d4d6fbbdef199380abeae3927 Mon Sep 17 00:00:00 2001
From: Claude Meny <claude.meny@irap.omp.eu>
Date: Mon, 15 Feb 2021 11:02:58 +0100
Subject: [PATCH] Update textbook.fr.md

---
 .../40.classical-mechanics/10.main/textbook.fr.md            | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/40.classical-mechanics/10.main/textbook.fr.md b/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/40.classical-mechanics/10.main/textbook.fr.md
index cb88475a7..57ec9d440 100644
--- a/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/40.classical-mechanics/10.main/textbook.fr.md
+++ b/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/40.classical-mechanics/10.main/textbook.fr.md
@@ -211,4 +211,9 @@ $`\overrightarrow{L}=\begin{vmatrix}
 x & y & z\\
 p_x & p_y & p_z\end{vmatrix}`$
 
+$`\vec{U}\land\vec{V}=\begin{vmatrix} \overrightarrow{e_1}&\overrightarrow{e_2}&\overrightarrow{e_3}\\
+U_1 & U_2 & U_3\\V_1 & V_2 & V_3\end{vmatrix}`$
+$`=U_1V_2\,\overrightarrow{e_3}+U_2V_3\,\overrightarrow{e_1}+U_3V_1\,\overrightarrow{e_2}`$
+$`-\,U_1V_3\,\overrightarrow{e_2}-U_2V_1\,\overrightarrow{e_3}-U_3V_2\,\overrightarrow{e_1}`$
+