diff --git a/Algo/Séminaire/Chapter 3 - Case analysis.md b/Algo/Séminaire/Chapter 3 - Case analysis.md
index 7c9f6bf..d6dffa6 100644
--- a/Algo/Séminaire/Chapter 3 - Case analysis.md	
+++ b/Algo/Séminaire/Chapter 3 - Case analysis.md	
@@ -13,6 +13,6 @@ if cond then expr1 else expr2
 
 # let abs(x) = 
 	if x>0 then x
-	else then x=x+(-x)+(-x) ;;;
+	else -x ;;;
 
 ```