Update 12.temporary_ins/40.classical-mechanics/30.n3/07.coherence/textbook.fr.md

12.temporary_ins/40.classical-mechanics/30.n3/07.coherence/textbook.fr.md

@@ -720,7 +720,7 @@ $`\cos\left(t\sqrt{\dfrac{g}{\mathscr{l}}}\right)=\cos\left(t\sqrt{\dfrac{g}{\ma
 
 soit
 
-$`t\sqrt{\dfrac{g}{\mathscr{l}}}+T\sqrt{\dfrac{g}{\mathscr{l}}}=t\sqrt{\dfrac{g}{\mathscr{l}}}/2\pi`$
+$`t\sqrt{\dfrac{g}{\mathscr{l}}}+T\sqrt{\dfrac{g}{\mathscr{l}}}=t\sqrt{\dfrac{g}{\mathscr{l}}}+2\pi`$
 
 $`\Longrightarrow T=2\pi\,\sqrt{\dfrac{\mathscr{l}}{g}}`$