diff --git a/00.brainstorming-pedagogical-teams/45.synthesis-structuring/10.math-tools/30.n3/10.brainstorming/01.p1/textbook.fr.md b/00.brainstorming-pedagogical-teams/45.synthesis-structuring/10.math-tools/30.n3/10.brainstorming/01.p1/textbook.fr.md
index c6494da49..a227880a1 100644
--- a/00.brainstorming-pedagogical-teams/45.synthesis-structuring/10.math-tools/30.n3/10.brainstorming/01.p1/textbook.fr.md
+++ b/00.brainstorming-pedagogical-teams/45.synthesis-structuring/10.math-tools/30.n3/10.brainstorming/01.p1/textbook.fr.md
@@ -55,7 +55,7 @@ Les *outils mathématiques de niveaux 1 et 2* **$`+`$** :
   **$`\sin\theta=\dfrac{e^{\,i\theta}-e^{\,-i\theta}}{2i}`$**
   <br>    
   et fonctions hyperboliques    
-  **$`\cosh(x)=\dfrac{e^x-+e^{\,- x}}{2}`$**   
+  **$`\cosh(x)=\dfrac{e^x+e^{\,- x}}{2}`$**   
   **$`\sinh(x)=\dfrac{e^x-e^{\,- x}}{2}`$**
 
 * **$`e^0=1 \quad , \quad`$**