{"id":1165,"date":"2019-04-19T17:39:13","date_gmt":"2019-04-19T15:39:13","guid":{"rendered":"https:\/\/www.mathweb.fr\/euclide\/?p=1165"},"modified":"2022-10-25T09:11:56","modified_gmt":"2022-10-25T07:11:56","slug":"section-dun-cube-par-un-plan-defini-par-3-points-sur-differentes-faces","status":"publish","type":"post","link":"https:\/\/www.mathweb.fr\/euclide\/2019\/04\/19\/section-dun-cube-par-un-plan-defini-par-3-points-sur-differentes-faces\/","title":{"rendered":"Section d&rsquo;un cube par un plan d\u00e9fini par 3 points sur diff\u00e9rentes faces"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Nous allons voir dans cet article comment trouver la section d&rsquo;un cube par un plan quand on conna\u00eet 3 points sur 3 ar\u00eates de ce cube, chacun des points n&rsquo;\u00e9tant pas sur une face o\u00f9 se trouve l&rsquo;un des deux autres.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube01.png\" rel=\"sectionCubePlan\" data-fancybox=\"gallery\"><img loading=\"lazy\" decoding=\"async\" width=\"293\" height=\"300\" src=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube01-293x300.png\" alt=\"\" class=\"wp-image-1166\" srcset=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube01-293x300.png 293w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube01-300x307.png 300w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube01-600x614.png 600w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube01-768x785.png 768w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube01-1001x1024.png 1001w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube01.png 1192w\" sizes=\"auto, (max-width: 293px) 100vw, 293px\" \/><\/a><figcaption>On souhaite trouver la section du cube par le plan (IJK)<\/figcaption><\/figure>\n<\/div>\n\n\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_85 counter-hierarchy ez-toc-counter ez-toc-white ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Au menu sur cette page...<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.mathweb.fr\/euclide\/2019\/04\/19\/section-dun-cube-par-un-plan-defini-par-3-points-sur-differentes-faces\/#Etape_1_on_projette_orthogonalement_un_point_sur_larete_parallele_a_celle_ou_il_se_trouve_et_contenue_dans_une_face_ou_se_trouve_lun_des_deux_autres_points\" >\u00c9tape 1 : on projette orthogonalement un point sur l&rsquo;ar\u00eate parall\u00e8le \u00e0 celle o\u00f9 il se trouve et contenue dans une face o\u00f9 se trouve l&rsquo;un des deux autres points.<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.mathweb.fr\/euclide\/2019\/04\/19\/section-dun-cube-par-un-plan-defini-par-3-points-sur-differentes-faces\/#Etape_2_on_trace_un_triangle_passant_par_le_sommet_oppose_a_la_face_contenant_le_point_choisi_et_son_projete\" >\u00c9tape 2 : on trace un triangle passant par le sommet oppos\u00e9 \u00e0 la face contenant le point choisi et son projet\u00e9.<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.mathweb.fr\/euclide\/2019\/04\/19\/section-dun-cube-par-un-plan-defini-par-3-points-sur-differentes-faces\/#Etape_4_on_trouve_enfin_un_point_qui_appartient_a_la_section_cherchee\" >\u00c9tape 4 : on trouve enfin un point qui appartient \u00e0 la section cherch\u00e9e.<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.mathweb.fr\/euclide\/2019\/04\/19\/section-dun-cube-par-un-plan-defini-par-3-points-sur-differentes-faces\/#Etape_5_on_trace_des_paralleles\" >\u00c9tape 5 : on trace des parall\u00e8les<\/a><\/li><\/ul><\/nav><\/div>\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Etape_1_on_projette_orthogonalement_un_point_sur_larete_parallele_a_celle_ou_il_se_trouve_et_contenue_dans_une_face_ou_se_trouve_lun_des_deux_autres_points\"><\/span>\u00c9tape 1 : on projette orthogonalement un point sur l&rsquo;ar\u00eate parall\u00e8le \u00e0 celle o\u00f9 il se trouve et contenue dans une face o\u00f9 se trouve l&rsquo;un des deux autres points.<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Ici, on va projeter le point J sur [BF] car [BF] est contenue dans une face o\u00f9 se trouve K. On obtient un point que l&rsquo;on nomme \\(P_1\\).<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube02.png\" rel=\"sectionCubePlan\" data-fancybox=\"gallery\"><img loading=\"lazy\" decoding=\"async\" width=\"293\" height=\"300\" src=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube02-293x300.png\" alt=\"\" class=\"wp-image-1167\" srcset=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube02-293x300.png 293w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube02-300x307.png 300w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube02-600x614.png 600w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube02-768x785.png 768w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube02-1001x1024.png 1001w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube02.png 1192w\" sizes=\"auto, (max-width: 293px) 100vw, 293px\" \/><\/a><figcaption>Projet\u00e9 orthogonal d&rsquo;un point sur une ar\u00eate oppos\u00e9e<\/figcaption><\/figure>\n<\/div>\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Etape_2_on_trace_un_triangle_passant_par_le_sommet_oppose_a_la_face_contenant_le_point_choisi_et_son_projete\"><\/span>\u00c9tape 2 : on trace un triangle passant par le sommet oppos\u00e9 \u00e0 la face contenant le point choisi et son projet\u00e9.<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Ici, on trace \\((AP_1)\\) et \\((IJ)\\). Elles sont coplanaires et non parall\u00e8les donc se coupent en un point \\(P_2\\).<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube03.png\" rel=\"sectionCubePlan\" data-fancybox=\"gallery\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"191\" src=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube03-300x191.png\" alt=\"\" class=\"wp-image-1168\" srcset=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube03-300x191.png 300w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube03-600x382.png 600w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube03-768x489.png 768w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube03-1024x652.png 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption>On trace un triangle<\/figcaption><\/figure>\n<\/div>\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Etape_4_on_trouve_enfin_un_point_qui_appartient_a_la_section_cherchee\"><\/span>\u00c9tape 4 : on trouve enfin un point qui appartient \u00e0 la section cherch\u00e9e.<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Les points K et \\(P_2\\) appartiennent \u00e0 la m\u00eame face (ABFE) donc la droite \\((KP_2)\\) coupe l&rsquo;ar\u00eate [AE] (car elles ne sont pas parall\u00e8les). On obtient alors le point \\(P_3\\).<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube04.png\" rel=\"sectionCubePlan\" data-fancybox=\"gallery\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"191\" src=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube04-300x191.png\" alt=\"\" class=\"wp-image-1169\" srcset=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube04-300x191.png 300w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube04-600x382.png 600w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube04-768x489.png 768w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube04-1024x652.png 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption>Un point appartenant \u00e0 la section<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">On a ainsi l&rsquo;intersection des plans (IJK) et (ADHE):<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube05.png\" rel=\"sectionCubePlan\" data-fancybox=\"gallery\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"191\" src=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube05-300x191.png\" alt=\"\" class=\"wp-image-1170\" srcset=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube05-300x191.png 300w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube05-600x382.png 600w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube05-768x489.png 768w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube05-1024x652.png 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption>Intersection d&rsquo;une face du cube avec le plan (IJK)<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">ainsi que celle des plans (IJK) et (ABFE):<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube06.png\" rel=\"sectionCubePlan\" data-fancybox=\"gallery\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"191\" src=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube06-300x191.png\" alt=\"\" class=\"wp-image-1171\" srcset=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube06-300x191.png 300w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube06-600x382.png 600w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube06-768x489.png 768w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube06-1024x652.png 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption>Intersection d&rsquo;une autre face du cube avec (IJK)<\/figcaption><\/figure>\n<\/div>\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Etape_5_on_trace_des_paralleles\"><\/span>\u00c9tape 5 : on trace des parall\u00e8les<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">On trace maintenant la droite parall\u00e8le \u00e0 \\((KP_3)\\) passant par J : elle coupe l&rsquo;ar\u00eate [DC] en \\(P_4\\):<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube07.png\" rel=\"sectionCubePlan\" data-fancybox=\"gallery\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"191\" src=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube07-300x191.png\" alt=\"\" class=\"wp-image-1172\" srcset=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube07-300x191.png 300w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube07-600x382.png 600w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube07-768x489.png 768w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube07-1024x652.png 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption>On trace une parall\u00e8le pour trouver un autre c\u00f4t\u00e9 de la section du cube par le plan (IJK)<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">On trace ensuite \\([IP_4]\\) qui est un autre c\u00f4t\u00e9 de la section cherch\u00e9e:<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a class=\"sectionCubePlan\" href=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube08.png\" rel=\"sectionCubePlan\" data-fancybox=\"gallery\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"191\" src=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube08-300x191.png\" alt=\"\" class=\"wp-image-1181\" srcset=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube08-300x191.png 300w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube08-600x382.png 600w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube08-768x489.png 768w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube08-1024x652.png 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">Puis la parall\u00e8le \u00e0 \\((IP_3)\\) passant par J, qui coupe [GF] en \\(P_5\\):<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube09.png\" rel=\"sectionCubePlan\" data-fancybox=\"gallery\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"191\" src=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube09-300x191.png\" alt=\"\" class=\"wp-image-1175\" srcset=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube09-300x191.png 300w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube09-600x382.png 600w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube09-768x489.png 768w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube09-1024x652.png 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption>On trace une deuxi\u00e8me parall\u00e8le<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">On trace enfin \\([KP_5]\\) qui ferme la section cherch\u00e9e:<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube10.png\" rel=\"sectionCubePlan\" data-fancybox=\"gallery\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"191\" src=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube10-300x191.png\" alt=\"\" class=\"wp-image-1176\" srcset=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube10-300x191.png 300w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube10-600x382.png 600w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube10-768x489.png 768w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/cube10-1024x652.png 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption>La section est d\u00e9sormais ferm\u00e9e<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">La section du cube par le plan (IJK) est le polygone \\(KP_5JP_4IP_3\\):<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><a href=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/section-cube-plan.png\" rel=\"sectionCubePlan\" data-fancybox=\"gallery\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"197\" src=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/section-cube-plan-300x197.png\" alt=\"\" class=\"wp-image-1177\" srcset=\"https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/section-cube-plan-300x197.png 300w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/section-cube-plan-600x393.png 600w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/section-cube-plan-768x503.png 768w, https:\/\/www.mathweb.fr\/euclide\/wp-content\/uploads\/2019\/04\/section-cube-plan-1024x671.png 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption>La section du cube par le plan est obtenue<\/figcaption><\/figure>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>Nous allons voir dans cet article comment trouver la section d&rsquo;un cube par un plan quand on conna\u00eet 3 points sur 3 ar\u00eates de ce cube, chacun des points n&rsquo;\u00e9tant pas sur une face o\u00f9 se trouve l&rsquo;un des deux autres. \u00c9tape 1 : on projette orthogonalement un point sur [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[21,6],"tags":[99,100,98],"class_list":["post-1165","post","type-post","status-publish","format-standard","hentry","category-enseignement","category-mathematiques","tag-cube","tag-plan","tag-solide"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.9 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Section d&#039;un cube par un plan d\u00e9fini par 3 points sur diff\u00e9rentes faces - Mathweb.fr<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" 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