From a2d6bb97ff546f3443620a6dc1d94dadbd734c3c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E7=8E=8B=E8=BD=B2=E6=A5=A0?= <wkn339224@qq.com>
Date: Sun, 11 Jan 2026 23:46:17 +0800
Subject: [PATCH] vault backup: 2026-01-11 23:46:17

---
 素材/秩的不等式.md | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/素材/秩的不等式.md b/素材/秩的不等式.md
index fd57403..3d28b8c 100644
--- a/素材/秩的不等式.md
+++ b/素材/秩的不等式.md
@@ -20,7 +20,7 @@ $$ \operatorname{rank}(AB) \geq \operatorname{rank} A + \operatorname{rank} B -
 
 设 $A_{n \times n}$， $B_{n \times n}$，则
 
-$$(1)\ rank  
+$$(1)\ \mathrm{rank}  
 
 \begin{bmatrix}
 A \\
@@ -32,21 +32,21 @@ B
 \end{bmatrix} \geq \text{rank } B
 $$
 
-$$(2)\ rank  
+$$(2)\ \mathrm{rank}  
 \begin{bmatrix}
 A & 0 \\
 0 & B
 \end{bmatrix} = \text{rank } A + \text{rank } B
 $$
 
-$$(3)\ rank  
+$$(3)\ \mathrm{rank}  
 \begin{bmatrix}
 A & E_n \\
 0 & B
 \end{bmatrix} \geq \text{rank } A + \text{rank } B
 $$
 
-$$(4)\ rank  
+$$(4)\ \mathrm{rank}  
 \begin{bmatrix}
 A & 0 \\
 0 & B