vault backup: 2025-12-17 17:03:56

2025-12-02.md

@@ -31,16 +31,16 @@ Let $A$ and $B$ be sets
 sharing some but not all elements.
 
 * $A \cap B \neq \varnothing$:
-    The intersection of $A$ and $B$ is nonempty
+    "The intersection of $A$ and $B$ is nonempty"
     (They share at least one element).
 
 * $A \not\subseteq B$:
-    $A$ is not a subset of $B$
+    "$A$ is not a subset of $B$"
     ($A$ has at least one element not in $B$).
     Equivalent to $A \setminus B \neq \varnothing$.
 
 * $B \not\subseteq A$:
-    $B$ is not a subset of $A$
+    "$B$ is not a subset of $A$"
     ($B$ has at least one element not in $A$).
     Equivalent to $B \setminus A \neq \varnothing$.