diff --git a/doc/src/week48/week48.do.txt b/doc/src/week48/week48.do.txt
index 2cbfb57a5..738468c5d 100644
--- a/doc/src/week48/week48.do.txt
+++ b/doc/src/week48/week48.do.txt
@@ -610,7 +610,7 @@ can be written as
 \lambda_3 \\
 \dots \\
 \lambda_n \\
-\end{bmatrix}\wedge 
+\end{bmatrix} \preceq
 \begin{bmatrix} 0 \\
 0 \\
 0 \\