diff --git a/linear-algebra/knowledge/2-matrix/matrix.pdf b/linear-algebra/knowledge/2-matrix/matrix.pdf
index 33e5983..a0436e1 100644
Binary files a/linear-algebra/knowledge/2-matrix/matrix.pdf and b/linear-algebra/knowledge/2-matrix/matrix.pdf differ
diff --git a/linear-algebra/knowledge/2-matrix/matrix.tex b/linear-algebra/knowledge/2-matrix/matrix.tex
index ef1dbc7..339d529 100644
--- a/linear-algebra/knowledge/2-matrix/matrix.tex
+++ b/linear-algebra/knowledge/2-matrix/matrix.tex
@@ -296,7 +296,7 @@ $A^*=\left(
 \begin{itemize}
     \item 任何方阵都有伴随矩阵，其中$AA^*=A^*A=\vert A\vert E$。
     \item $A^*=\vert A\vert A^{-1}$，$A^{-1}=\dfrac{1}{\vert A\vert}A^*$，$A=\vert A\vert(A^*)^{-1}$。
-    \item $\vert A^*\vert=\vert A\vert^{n-1}$，$(kA)(kA)^*=\vert kA\vert E$，$A^T(A^T)^*=\vert A^T\vert E$，$A^{-1}(A^{-1})^*=\vert A^{-1}\vert E$，$A^*(A^*)^*=\vert A^*\vert E$。
+    \item $\vert A^*\vert=\vert A\vert^{n-1}$，$(kA)^*=k^{n-1}A^*$，$(kA)(kA)^*=\vert kA\vert E$，$A^T(A^T)^*=\vert A^T\vert E$，$A^{-1}(A^{-1})^*=\vert A^{-1}\vert E$，$A^*(A^*)^*=\vert A^*\vert E$。
     \item $(A^T)^*=(A^*)^T$，$(A^{-1})^*=(A^*)^{-1}$，$(AB)^*=B^*A^*$，$(A^*)^*=\vert A\vert^{n-2}A$。
 \end{itemize}