Update 12.temporary_ins/32.sets-systems/30.n3/20.systems/10.main/textbook.fr.md

12.temporary_ins/32.sets-systems/30.n3/20.systems/10.main/textbook.fr.md

@@ -10,6 +10,18 @@ lessons:
       order: 1
 ---
 
+<!--caligraphie de l'intégrale double curviligne-->
+
+$`\def\bigt{\large{t}\normalsize}`$
+$`\def\dens{\large{\varrho}\normalsize}`$
+$`\def\oiint{\displaystyle\mathop{{\iint}\mkern-18mu \scriptsize \bigcirc}}`$
+$`\def\Ltau{\Large{\tau}\normalsize}`$
+$`\def\Sopen{\mathscr{S}_{\smile}}`$
+$`\def\Sclosed{\mathscr{S}_{\displaystyle\tiny\bigcirc}}`$
+$`\def\Ssclosed{\mathscr{S}_{\scriptsize\bigcirc}}`$
+$`\def\PSopen{\mathscr{S}_{\smile}}`$
+$`\def\PSclosed{\mathscr{S}_{\displaystyle\tiny\bigcirc}}`$
+
 <!---------
 !!!!  <details>
 !!!! <summary> Cours en construction, non validé à ce stade </summary>