Update cheatsheet.fr.md

12.temporary_ins/40.classical-mechanics/20.n2/10.framework-of-classical-mechanics-2/20.overview/cheatsheet.fr.md

@@ -248,19 +248,19 @@ et test équivalent en html, pas en image
 
 
 <p style="font-family:'Times New Roman';font-weight:bold;font-size:1.15rem;text-align:left;color:#009933">Tous les observateurs partagent</p>
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 <p style="font-family:'Times New Roman';font-weight:bold;font-size:1.15rem;text-align:left;color:#cccccc">un <span style="color:#0033cc"> invariant spatial<br>
 <span style="font-family:'Times New Roman';margin-left:30px;font-weight:bold;font-size:0.85rem;text-align:right;color:#6699ff">entre deux points A et B de l'espace </span><br>
 <span style="font-family:'Times New Roman';font-weight:bold;font-size:1.15rem;color:#cccccc">appelé 
 </span><span style="font-family:'Times New Roman';font-weight:bold;font-size:1.15rem;left;color:#cc3300"> longueur  l<sub>AB</sub>
 </span><span style="font-family:'Times New Roman';font-weight:bold;font-size:0.85rem;color:#6699ff"> entre ces deux points.</span></p>
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 <p style="font-family:'Times New Roman';font-weight:bold;font-size:1.15rem;text-align:left;color:#cccccc">un <span style="color:#0033cc"> invariant temporel<br>
 <span style="font-family:'Times New Roman';margin-left:30px;font-weight:bold;font-size:0.85rem;text-align:right;color:#6699ff">entre deux instants t<sub>1</sub> et t<sub>2</sub> du temps</span><br>
 <span style="font-family:'Times New Roman';font-weight:bold;font-size:1.15rem;color:#cccccc">appelé 
 </span><span style="font-family:'Times New Roman';font-weight:bold;font-size:1.15rem;left;color:#cc3300"> durée  t<sub>2</sub> - t<sub>1</sub></span>
 <span style="font-family:'Times New Roman';font-weight:bold;font-size:0.85rem;color:#6699ff"> entre ces deux instants.</span></p>
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