Update cheatsheet.en.md

01.curriculum/01.physics-chemistry-biology/03.Niv3/02.Geometrical-optics/01.geometrical-optics-general/01.geometrical-optics-validity/02.geometrical-optics-domain-of-validity-overview/cheatsheet.en.md

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 title: 'The optics for everyday life'
 media_order: 'chrono_text_opt_geo_fr_v2.jpeg,sciences_optique_rays_fr.jpeg,chrono_opt_geo_fr_v2.jpeg,Opt_geom_1.jpg,OG_intro.mp3,OG_intro.ogg'
+published : true
+visible : false
 ---
 
 ### The optics for everyday life