src/ZF/EquivClass.thy
changeset 76214 0c18df79b1c8
parent 76213 e44d86131648
child 76215 a642599ffdea
--- a/src/ZF/EquivClass.thy	Tue Sep 27 16:51:35 2022 +0100
+++ b/src/ZF/EquivClass.thy	Tue Sep 27 17:03:23 2022 +0100
@@ -92,7 +92,7 @@
 by (unfold equiv_def, blast)
 
 lemma equiv_class_eq_iff:
-     "equiv(A,r) \<Longrightarrow> <x,y>: r \<longleftrightarrow> r``{x} = r``{y} & x \<in> A & y \<in> A"
+     "equiv(A,r) \<Longrightarrow> <x,y>: r \<longleftrightarrow> r``{x} = r``{y} \<and> x \<in> A \<and> y \<in> A"
 by (blast intro: eq_equiv_class equiv_class_eq dest: equiv_type)
 
 lemma eq_equiv_class_iff: