{"id":14913,"date":"2025-06-10T21:32:14","date_gmt":"2025-06-10T14:32:14","guid":{"rendered":"https:\/\/www.ckconitsha.com\/vn\/?p=14913"},"modified":"2025-07-05T17:50:06","modified_gmt":"2025-07-05T10:50:06","slug":"cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc","status":"publish","type":"post","link":"https:\/\/www.ckconitsha.com\/vn\/cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc\/","title":{"rendered":"C\u00e1ch t\u00ecm b\u1ed9i chung nh\u1ecf nh\u1ea5t c\u1ee7a 3 s\u1ed1 c\u1ef1c nhanh ch\u1ec9 3 b\u01b0\u1edbc"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_79_2 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.ckconitsha.com\/vn\/cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc\/#Xem_lai_ly_thuyet_ve_boi_so_nho_nhat_cua_3_so\" >Xem l\u1ea1i l\u00fd thuy\u1ebft v\u1ec1 b\u1ed9i s\u1ed1 nh\u1ecf nh\u1ea5t c\u1ee7a 3 s\u1ed1<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.ckconitsha.com\/vn\/cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc\/#Khi_ban_can_tim_boi_so_chung_nho_nhat_trong_so_3_so\" >Khi b\u1ea1n c\u1ea7n t\u00ecm b\u1ed9i s\u1ed1 chung nh\u1ecf nh\u1ea5t trong s\u1ed1 3 s\u1ed1<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.ckconitsha.com\/vn\/cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc\/#Huong_dan_ve_cach_tim_boi_so_nho_nhat_cua_3_so\" >H\u01b0\u1edbng d\u1eabn v\u1ec1 c\u00e1ch t\u00ecm b\u1ed9i s\u1ed1 nh\u1ecf nh\u1ea5t c\u1ee7a 3 s\u1ed1<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.ckconitsha.com\/vn\/cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc\/#Cach_tim_3_so_pho_bien_nho_nhat_cho_may_tinh\" >C\u00e1ch t\u00ecm 3 s\u1ed1 ph\u1ed5 bi\u1ebfn nh\u1ecf nh\u1ea5t cho m\u00e1y t\u00ednh<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.ckconitsha.com\/vn\/cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc\/#Tap_the_duc_de_tim_boi_so_chung_nho_nhat_trong_so_3_so_tu_dong\" >T\u1eadp th\u1ec3 d\u1ee5c \u0111\u1ec3 t\u00ecm b\u1ed9i s\u1ed1 chung nh\u1ecf nh\u1ea5t trong s\u1ed1 3 s\u1ed1 t\u1ef1 \u0111\u1ed9ng<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.ckconitsha.com\/vn\/cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc\/#Bai_tap_1_Tim_BCNNs\" >B\u00e0i t\u1eadp 1: T\u00ecm BCNN&#8217;s<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.ckconitsha.com\/vn\/cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc\/#Bai_tap_2_Tim_so_X_tu_nhien_lon_nhat_biet_rang\" >B\u00e0i t\u1eadp 2: T\u00ecm s\u1ed1 X t\u1ef1 nhi\u00ean l\u1edbn nh\u1ea5t, bi\u1ebft r\u1eb1ng:<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.ckconitsha.com\/vn\/cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc\/#Bai_tap_3_Tim_so_tu_nhien_x\" >B\u00e0i t\u1eadp 3: T\u00ecm s\u1ed1 t\u1ef1 nhi\u00ean x;<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/www.ckconitsha.com\/vn\/cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc\/#Bai_tap_4\" >B\u00e0i t\u1eadp 4<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/www.ckconitsha.com\/vn\/cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc\/#Bai_tap_5\" >B\u00e0i t\u1eadp 5<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/www.ckconitsha.com\/vn\/cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc\/#Mot_so_ghi_chu_theo_cach_nho_nhat_de_tim_3_so\" >M\u1ed9t s\u1ed1 ghi ch\u00fa theo c\u00e1ch nh\u1ecf nh\u1ea5t \u0111\u1ec3 t\u00ecm 3 s\u1ed1<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/www.ckconitsha.com\/vn\/cach-tim-boi-chung-nho-nhat-cua-3-so-cuc-nhanh-chi-3-buoc\/#Ket_luan\" >K\u1ebft lu\u1eadn<\/a><\/li><\/ul><\/nav><\/div>\n<\/p>\n<p>C\u00e1ch nh\u1ecf nh\u1ea5t \u0111\u1ec3 t\u00ecm th\u1ea5y T\u01b0\u1edbng 3 -Ti\u00eau ch\u00ed l\u00e0 m\u1ed9t trong nh\u1eefng v\u1ea5n \u0111\u1ec1 l\u1edbp 6 m\u00e0 h\u1ecd s\u1ebd g\u1eb7p ph\u1ea3i. V\u00ec v\u1eady, \u0111\u1ec3 gi\u00fap h\u1ecdc sinh chinh ph\u1ee5c lo\u1ea1i to\u00e1n n\u00e0y m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3, \u0111\u1ea1t \u0111\u01b0\u1ee3c k\u1ebft qu\u1ea3 t\u1ed1t, h\u00e3y \u00e1p d\u1ee5ng c\u00e1c b\u01b0\u1edbc m\u00e0 kh\u1ec9 chia s\u1ebb trong b\u00e0i vi\u1ebft sau.<\/p>\n<p>                        Xem t\u1ea5t c\u1ea3<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Xem_lai_ly_thuyet_ve_boi_so_nho_nhat_cua_3_so\"><\/span>Xem l\u1ea1i l\u00fd thuy\u1ebft v\u1ec1 b\u1ed9i s\u1ed1 nh\u1ecf nh\u1ea5t c\u1ee7a 3 s\u1ed1<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>B\u1ed9i s\u1ed1 chung nh\u1ecf nh\u1ea5t l\u00e0 g\u00ec? B\u1ed9i s\u1ed1 chung nh\u1ecf nh\u1ea5t (ho\u1eb7c b\u1ed9i s\u1ed1 ph\u1ed5 bi\u1ebfn nh\u1ecf nh\u1ea5t c\u1ee7a hai ho\u1eb7c nhi\u1ec1u s\u1ed1 nguy\u00ean) l\u00e0 s\u1ed1 nguy\u00ean d\u01b0\u01a1ng nh\u1ecf nh\u1ea5t chia cho t\u1ea5t c\u1ea3 c\u00e1c s\u1ed1 nguy\u00ean d\u01b0\u01a1ng \u0111ang \u0111\u01b0\u1ee3c xem x\u00e9t. D\u1ec5 d\u00e0ng hi\u1ec3u, \u0111\u00e2y l\u00e0 con s\u1ed1 c\u00f3 th\u1ec3 chia h\u1ebft b\u1edfi t\u1ea5t c\u1ea3 c\u00e1c s\u1ed1 nguy\u00ean d\u01b0\u01a1ng \u0111\u01b0\u1ee3c xem x\u00e9t (kh\u00f4ng ph\u1ea3i c\u00f2n l\u1ea1i).<\/p>\n<p>C\u00e1c b\u1ed9i s\u1ed1 nh\u1ecf nh\u1ea5t c\u1ee7a 3 s\u1ed1 l\u00e0 g\u00ec? T\u01b0\u01a1ng t\u1ef1 nh\u01b0 kh\u00e1i ni\u1ec7m tr\u00ean, m\u1ee9c t\u1ed1i thi\u1ec3u c\u1ee7a 3 s\u1ed1 l\u00e0 m\u1ed9t s\u1ed1 nguy\u00ean d\u01b0\u01a1ng c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c chia cho c\u1ea3 3 s\u1ed1 \u0111\u01b0\u1ee3c xem x\u00e9t.<\/p>\n<p>V\u00ed d\u1ee5, b\u1ed9i s\u1ed1 chung nh\u1ecf nh\u1ea5t c\u1ee7a (12, 16, 48) l\u00e0 48.<\/p>\n<h2 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Khi_ban_can_tim_boi_so_chung_nho_nhat_trong_so_3_so\"><\/span>Khi b\u1ea1n c\u1ea7n t\u00ecm b\u1ed9i s\u1ed1 chung nh\u1ecf nh\u1ea5t trong s\u1ed1 3 s\u1ed1<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p dir=\"ltr\">\u0110\u1ed1i v\u1edbi v\u1ea5n \u0111\u1ec1 t\u00ecm BCNN g\u1ed3m 3 s\u1ed1, n\u00f3 th\u01b0\u1eddng \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng \u0111\u1ec3 gi\u1ea3i quy\u1ebft c\u00e1c v\u1ea5n \u0111\u1ec1 mu\u1ed1n gi\u1ea3m thi\u1ec3u s\u1ed1 \u0111\u1ec3 th\u1ef1c hi\u1ec7n t\u00ednh to\u00e1n. Th\u1ef1c hi\u1ec7n c\u00e1c lo\u1ea1i t\u00ednh to\u00e1n s\u1ed1 nguy\u00ean, c\u00e1c b\u00e0i t\u1eadp to\u00e1n v\u1edbi c\u00e1c t\u1eeb v\u00e0 c\u00e2u \u0111\u1ed1 c\u0169ng th\u01b0\u1eddng s\u1eed d\u1ee5ng c\u00e1ch n\u00e0y \u0111\u1ec3 t\u00ecm BCNN \u0111\u1ec3 gi\u1ea3i quy\u1ebft nhanh ch\u00f3ng.<\/p>\n<p dir=\"ltr\"><img decoding=\"async\" class=\"lazyload\" src=\"https:\/\/external-content.duckduckgo.com\/iu\/?u=https:\/\/vnmedia2.monkeyuni.net\/upload\/web\/img\/cach-tim-boi-chung-nho-nhat-3-so-1.jpg\" alt=\"T\u00ecm BCNN g\u1ed3m 3 s\u1ed1 \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng trong nhi\u1ec1u v\u1ea5n \u0111\u1ec1. (\u1ea2nh: B\u1ed9 s\u01b0u t\u1eadp Internet)\" width=\"100%\"><\/p>\n<h2 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Huong_dan_ve_cach_tim_boi_so_nho_nhat_cua_3_so\"><\/span>H\u01b0\u1edbng d\u1eabn v\u1ec1 c\u00e1ch t\u00ecm b\u1ed9i s\u1ed1 nh\u1ecf nh\u1ea5t c\u1ee7a 3 s\u1ed1<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p dir=\"ltr\">V\u1ec1 c\u01a1 b\u1ea3n, c\u00e1ch \u0111\u1ec3 t\u00ecm BCNN c\u1ee7a 3 s\u1ed1 c\u0169ng \u0111\u01a1n gi\u1ea3n nh\u01b0 c\u00e1c v\u1ea5n \u0111\u1ec1 t\u00ecm ki\u1ebfm BCNN th\u00f4ng th\u01b0\u1eddng. C\u1ee5 th\u1ec3 l\u00e0m theo c\u00e1c b\u01b0\u1edbc sau:<\/p>\n<ul>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">B\u01b0\u1edbc 1: Ph\u00e2n t\u00edch t\u1eebng s\u1ed1 th\u00e0nh c\u00e1c y\u1ebfu t\u1ed1 ch\u00ednh<\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">B\u01b0\u1edbc 2: T\u00ecm c\u00e1c y\u1ebfu t\u1ed1 ch\u00ednh ph\u1ed5 bi\u1ebfn v\u00e0 ri\u00eang t\u01b0 c\u1ee7a 3 s\u1ed1<\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">B\u01b0\u1edbc 3: Ti\u1ebfn h\u00e0nh s\u1ea3n ph\u1ea9m c\u1ee7a c\u00e1c y\u1ebfu t\u1ed1 ch\u00ednh \u0111\u01b0\u1ee3c ch\u1ecdn, m\u1ed7i y\u1ebfu t\u1ed1 s\u1ebd l\u1ea5y ra s\u1ed1 m\u0169 cao nh\u1ea5t. T\u1ea1i th\u1eddi \u0111i\u1ec3m n\u00e0y, BCNN l\u00e0 s\u1ea3n ph\u1ea9m \u0111\u00f3.<\/p>\n<\/li>\n<\/ul>\n<p dir=\"ltr\">Ghi ch\u00fa:<\/p>\n<ul>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">N\u1ebfu c\u00e1c s\u1ed1 \u0111\u01b0\u1ee3c coi l\u00e0 c\u00e1c y\u1ebfu t\u1ed1 c\u00f9ng nhau, s\u1ea3n ph\u1ea9m c\u1ee7a nh\u1eefng con s\u1ed1 \u0111\u00f3 l\u00e0 bcnn.<\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">Trong tr\u01b0\u1eddng h\u1ee3p c\u00e1c s\u1ed1 \u0111\u00e3 cho, v\u1edbi s\u1ed1 l\u1edbn nh\u1ea5t l\u00e0 b\u1ed9i s\u1ed1 c\u1ee7a 2 s\u1ed1 c\u00f2n l\u1ea1i, BCNN c\u1ee7a ba s\u1ed1 l\u00e0 s\u1ed1 l\u1edbn nh\u1ea5t.<\/p>\n<\/li>\n<\/ul>\n<table style=\"border-collapse: collapse;width: 100.01%;background-color: #fbeeb8\" border=\"1\">\n<tr>\n<td style=\"width: 98.5932%\">\u0110\u1eebng b\u1ecf l\u1ee1 !! Ch\u01b0\u01a1ng tr\u00ecnh to\u00e1n h\u1ecdc b\u1eb1ng ti\u1ebfng Anh, gi\u00fap ph\u00e1t tri\u1ec3n t\u01b0 duy theo c\u00e1ch to\u00e0n di\u1ec7n nh\u1ea5t. Nh\u1eadn t\u1ed1i \u0111a 40% \u01b0u \u0111\u00e3i ngay t\u1ea1i \u0111\u00e2y!<img decoding=\"async\" style=\"margin-left: auto;margin-right: auto\" class=\"lazyload\" src=\"https:\/\/external-content.duckduckgo.com\/iu\/?u=https:\/\/vnmedia2.monkeyuni.net\/upload\/web\/img\/taimienphiMM.png\" width=\"185\"><\/td>\n<\/tr>\n<\/table>\n<h2 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Cach_tim_3_so_pho_bien_nho_nhat_cho_may_tinh\"><\/span>C\u00e1ch t\u00ecm 3 s\u1ed1 ph\u1ed5 bi\u1ebfn nh\u1ecf nh\u1ea5t cho m\u00e1y t\u00ednh<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p dir=\"ltr\">Ngo\u00e0i nhi\u1ec1u b\u01b0\u1edbc chung nh\u1ecf nh\u1ea5t c\u1ee7a 3 s\u1ed1 tr\u00ean, h\u1ecd c\u00f3 th\u1ec3 \u00e1p d\u1ee5ng ph\u01b0\u01a1ng ph\u00e1p t\u00ecm BCNN th\u00f4ng qua m\u00e1y t\u00ednh Casio 570 Plus.<\/p>\n<p dir=\"ltr\">\u0110\u00e2y l\u00e0 m\u1ed9t v\u00ed d\u1ee5 \u0111\u1ec3 m\u1ecdi ng\u01b0\u1eddi hi\u1ec3u th\u00eam.  <\/p>\n<p dir=\"ltr\"><em>T\u00ecm BCNN c\u1ee7a c\u00e1c s\u1ed1 sau:<\/em><\/p>\n<p dir=\"ltr\"><em>a) 10, 12, 15<\/em><\/p>\n<p dir=\"ltr\"><em>b) 8, 9, 11<\/em><\/p>\n<p dir=\"ltr\"><em>c) 24, 40, 168<\/em><\/p>\n<p dir=\"ltr\"><em>Gi\u1ea3i \u0111\u1ea5u tr\u00ean m\u00e1y t\u00ednh Casio 570 Plus s\u1ebd nh\u01b0 sau:<\/em><\/p>\n<p dir=\"ltr\"><img decoding=\"async\" class=\"lazyload\" src=\"https:\/\/external-content.duckduckgo.com\/iu\/?u=https:\/\/vnmedia2.monkeyuni.net\/upload\/web\/img\/cach-tim-boi-chung-nho-nhat-3-so-2.jpg\" alt=\"T\u00ecm BCNN d\u1ef1a tr\u00ean m\u00e1y t\u00ednh s\u1ebd \u0111\u01a1n gi\u1ea3n h\u01a1n. (\u1ea2nh: B\u1ed9 s\u01b0u t\u1eadp Internet)\" width=\"100%\"><\/p>\n<h2 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Tap_the_duc_de_tim_boi_so_chung_nho_nhat_trong_so_3_so_tu_dong\"><\/span>T\u1eadp th\u1ec3 d\u1ee5c \u0111\u1ec3 t\u00ecm b\u1ed9i s\u1ed1 chung nh\u1ecf nh\u1ea5t trong s\u1ed1 3 s\u1ed1 t\u1ef1 \u0111\u1ed9ng<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p dir=\"ltr\">D\u01b0\u1edbi \u0111\u00e2y l\u00e0 m\u1ed9t b\u1ea3n t\u00f3m t\u1eaft c\u1ee7a m\u1ed9t s\u1ed1 b\u00e0i t\u1eadp li\u00ean quan \u0111\u1ebfn vi\u1ec7c t\u00ecm ki\u1ebfm BCNN g\u1ed3m 3 s\u1ed1 t\u1ef1 nhi\u00ean, b\u1ea1n c\u00f3 th\u1ec3 \u00e1p d\u1ee5ng c\u00e1c c\u00e1ch tr\u00ean \u0111\u1ec3 th\u1ef1c h\u00e0nh hi\u1ec7u qu\u1ea3:<\/p>\n<p dir=\"ltr\"><img decoding=\"async\" class=\"lazyload\" src=\"https:\/\/external-content.duckduckgo.com\/iu\/?u=https:\/\/vnmedia2.monkeyuni.net\/upload\/web\/img\/cach-tim-boi-chung-nho-nhat-3-so-3.jpg\" alt=\"Gi\u1ea3i t\u1eadp c\u00e1c b\u00e0i t\u1eadp \u0111\u1ec3 t\u00ecm BCNN c\u1ee7a 3 s\u1ed1 \u0111\u01a1n gi\u1ea3n. (\u1ea2nh: B\u1ed9 s\u01b0u t\u1eadp Internet)\" width=\"100%\"><\/p>\n<h3 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Bai_tap_1_Tim_BCNNs\"><\/span>B\u00e0i t\u1eadp 1: T\u00ecm BCNN&#8217;s<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p dir=\"ltr\">a) BCNN (8; 10; 20)<\/p>\n<p dir=\"ltr\">B) BCNN (56; 70; 126<\/p>\n<p dir=\"ltr\">c) BCNN (28; 20; 30)<\/p>\n<p dir=\"ltr\">D) BCNN (34; 32; 20)<\/p>\n<p dir=\"ltr\">e) BCNN (8; 9; 11)<\/p>\n<p dir=\"ltr\">f) BCNN (42; 70; 52)<\/p>\n<p dir=\"ltr\">g) BCNN (24; 40; 162)<\/p>\n<p dir=\"ltr\">h) BCNN (9; 10; 11)<\/p>\n<h3 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Bai_tap_2_Tim_so_X_tu_nhien_lon_nhat_biet_rang\"><\/span>B\u00e0i t\u1eadp 2: T\u00ecm s\u1ed1 X t\u1ef1 nhi\u00ean l\u1edbn nh\u1ea5t, bi\u1ebft r\u1eb1ng:<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p dir=\"ltr\">a) 420 \u22ee x v\u00e0 700 \u22ee x<\/p>\n<p dir=\"ltr\">b) 17 \u22ee x; 21 x v\u00e0 51 \u22ee x<\/p>\n<p dir=\"ltr\">c) 48 \u22ee x v\u00e0 60 \u22ee x<\/p>\n<p dir=\"ltr\">d) 8 \u22ee x; 25 \u22ee x v\u00e0 40 \u22ee x<\/p>\n<p dir=\"ltr\">e) 105 \u22ee x; 175 \u22ee x v\u00e0 385 \u22ee x<\/p>\n<p dir=\"ltr\">f) 12 \u22ee x; 15 \u22ee x v\u00e0 35 \u22ee x<\/p>\n<p dir=\"ltr\">g) 46 \u22ee x; 32 \u22ee x v\u00e0 56 x<\/p>\n<p dir=\"ltr\">h) 50 \u22ee x; 42 \u22ee x v\u00e0 38 \u22ee x<\/p>\n<p dir=\"ltr\">\n<h3 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Bai_tap_3_Tim_so_tu_nhien_x\"><\/span>B\u00e0i t\u1eadp 3: T\u00ecm s\u1ed1 t\u1ef1 nhi\u00ean x;<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p dir=\"ltr\">a) x \u2208 B (8) v\u00e0 x \u2264 30<\/p>\n<p dir=\"ltr\">b) x \u22ee 12 v\u00e0 50<\/p>\n<p dir=\"ltr\">c) x \u2208 B (15) v\u00e0 15<\/p>\n<p dir=\"ltr\">d) x \u22ee 14 v\u00e0 x &lt;92<\/p>\n<p dir=\"ltr\">e) x \u2208 B (12) v\u00e0 12<\/p>\n<p dir=\"ltr\">f) x \u22ee 9 v\u00e0 x &lt;40<\/p>\n<p dir=\"ltr\">g) x \u2208 B (5) v\u00e0 x \u2264100<\/p>\n<p dir=\"ltr\">h) x \u22ee 12 v\u00e0 24 \u2264 x 80<\/p>\n<h3 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Bai_tap_4\"><\/span>B\u00e0i t\u1eadp 4<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p dir=\"ltr\">T\u00ecm s\u1ed1 t\u1ef1 nhi\u00ean l\u1edbn nh\u1ea5t X th\u1ecfa m\u00e3n: 27 Division X d\u01b0 3; 38 Chia x d\u01b0 2 v\u00e0 49 Division X d\u01b0 1.<\/p>\n<h3 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Bai_tap_5\"><\/span>B\u00e0i t\u1eadp 5<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p dir=\"ltr\">T\u00ecm s\u1ed1 t\u1ef1 nhi\u00ean nh\u1ecf nh\u1ea5t X khi chia x cho c\u00e1c s\u1ed1 5; 7; 11, s\u1ed1 d\u01b0 l\u00e0 3; 4; 6.<\/p>\n<h2 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Mot_so_ghi_chu_theo_cach_nho_nhat_de_tim_3_so\"><\/span>M\u1ed9t s\u1ed1 ghi ch\u00fa theo c\u00e1ch nh\u1ecf nh\u1ea5t \u0111\u1ec3 t\u00ecm 3 s\u1ed1<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p dir=\"ltr\">Trong qu\u00e1 tr\u00ecnh gi\u1ea3i quy\u1ebft nhi\u1ec1u b\u00e0i t\u1eadp chung t\u1ed1i thi\u1ec3u c\u1ee7a 3 s\u1ed1, h\u1ecd c\u1ea7n l\u01b0u \u00fd m\u1ed9t s\u1ed1 v\u1ea5n \u0111\u1ec1 sau:<\/p>\n<p dir=\"ltr\"><img decoding=\"async\" class=\"lazyload\" src=\"https:\/\/external-content.duckduckgo.com\/iu\/?u=https:\/\/vnmedia2.monkeyuni.net\/upload\/web\/img\/cach-tim-boi-chung-nho-nhat-3-so-4.jpg\" alt=\"\u0110\u00e0o t\u1ea1o th\u01b0\u1eddng xuy\u00ean l\u00e0 quan tr\u1ecdng. (\u1ea2nh: Wikihow)\" width=\"100%\"><\/p>\n<ul>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">\u0110\u1ecdc k\u1ef9 v\u1ea5n \u0111\u1ec1: d\u01b0\u1edbi d\u1ea1ng to\u00e1n h\u1ecdc, vi\u1ec7c t\u00ecm ki\u1ebfm BCNN s\u1ebd c\u00f3 nhi\u1ec1u lo\u1ea1i b\u00e0i t\u1eadp kh\u00e1c nhau, v\u00ec v\u1eady h\u00e3y \u0111\u1ecdc k\u1ef9 v\u1ea5n \u0111\u1ec1 \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh v\u00e0 gi\u1ea3i quy\u1ebft v\u1ea5n \u0111\u1ec1 ch\u00ednh x\u00e1c h\u01a1n.<\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">Th\u1ef1c h\u00e0nh th\u01b0\u1eddng xuy\u00ean: V\u1edbi to\u00e1n h\u1ecdc t\u00ecm ki\u1ebfm 3 -Digit BCNN kh\u00f4ng qu\u00e1 kh\u00f3, nh\u01b0ng th\u1ef1c h\u00e0nh th\u01b0\u1eddng xuy\u00ean s\u1ebd gi\u00fap h\u1ecd gi\u1ea3i quy\u1ebft to\u00e1n h\u1ecdc nhanh h\u01a1n, c\u0169ng nh\u01b0 kh\u00f4ng nh\u1eadn \u0111\u01b0\u1ee3c ki\u1ebfn \u200b\u200bth\u1ee9c.<\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">Gi\u1ea3i c\u00e1c b\u00e0i t\u1eadp n\u00e2ng cao: Thay v\u00ec ch\u1ec9 xem x\u00e9t c\u00e1c h\u00ecnh th\u1ee9c to\u00e1n h\u1ecdc c\u01a1 b\u1ea3n t\u00ecm BCNN, h\u1ecd n\u00ean trau d\u1ed3i ki\u1ebfn \u200b\u200bth\u1ee9c v\u00e0 gi\u1ea3i quy\u1ebft c\u00e1c b\u00e0i t\u1eadp n\u00e2ng cao \u0111\u1ec3 chinh ph\u1ee5c nhi\u1ec1u b\u00e0i ki\u1ec3m tra \u0111\u1ec3 \u0111\u1ea1t \u0111\u01b0\u1ee3c k\u1ebft qu\u1ea3 t\u1ed1t.<\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">Kh\u00f4ng ph\u1ee5 thu\u1ed9c v\u00e0o m\u00e1y t\u00ednh: Nhi\u1ec1u sinh vi\u00ean th\u01b0\u1eddng t\u00ednh to\u00e1n c\u00e1c b\u00e0i t\u1eadp \u0111\u1ec3 t\u00ecm BCNN d\u1ef1a tr\u00ean m\u00e1y t\u00ednh Casio, nh\u01b0ng kh\u00f4ng n\u00ean qu\u00e1 ph\u1ee5 thu\u1ed9c v\u00e0o n\u00f3. Thay v\u00e0o \u0111\u00f3, ch\u1ec9 s\u1eed d\u1ee5ng \u0111\u1ec3 bi\u1ebft k\u1ebft qu\u1ea3 \u0111\u00fang hay sai \u0111\u1ec3 gi\u1ea3i quy\u1ebft to\u00e1n h\u1ecdc ch\u00ednh x\u00e1c h\u01a1n.<\/p>\n<\/li>\n<\/ul>\n<p>B\u00ean c\u1ea1nh \u0111\u00f3, b\u1ea1n n\u00ean th\u1ef1c h\u00e0nh c\u00e1c h\u00ecnh th\u1ee9c c\u1ee7a t\u00ednh to\u00e1n n\u00e0y th\u01b0\u1eddng xuy\u00ean h\u01a1n. B\u1ea1n c\u0169ng c\u00f3 th\u1ec3 d\u1ef1a v\u00e0o s\u1ef1 h\u1ed7 tr\u1ee3 c\u1ee7a ph\u1ea7n m\u1ec1m to\u00e1n h\u1ecdc tr\u1ef1c tuy\u1ebfn, ch\u1eb3ng h\u1ea1n nh\u01b0: <em>Shining Home &#8211; Gia \u0111\u00ecnh Anh Ng\u1eef Math, &#8230;<\/em><\/p>\n<p>Shining Home &#8211; Gia \u0111\u00ecnh Anh Ng\u1eef Math \u0111\u01b0\u1ee3c bi\u1ebft \u0111\u1ebfn nh\u01b0 m\u1ed9t ph\u1ea7n m\u1ec1m to\u00e1n h\u1ecdc ti\u1ebfng Anh cho tr\u1ebb em t\u1eeb m\u1eabu gi\u00e1o \u0111\u1ebfn cu\u1ed1i tr\u01b0\u1eddng ti\u1ec3u h\u1ecdc (ti\u1ebfp t\u1ee5c n\u00e2ng c\u1ea5p c\u00e1c t\u00ednh n\u0103ng kh\u00e1c). \u0110\u00e2y l\u00e0 m\u1ed9t \u1ee9ng d\u1ee5ng kh\u00f4ng ch\u1ec9 gi\u00fap tr\u1ebb em nhanh ch\u00f3ng n\u1eafm b\u1eaft ki\u1ebfn \u200b\u200bth\u1ee9c to\u00e1n h\u1ecdc, m\u00e0 c\u00f2n th\u1ef1c h\u00e0nh ng\u00f4n ng\u1eef th\u1ee9 hai (ti\u1ebfng Anh) theo c\u00e1ch m\u01b0\u1ee3t m\u00e0 v\u00e0 t\u1ef1 nhi\u00ean nh\u1ea5t.<\/p>\n<p>\u0110\u1ec3 \u0111\u01b0\u1ee3c l\u1eddi khuy\u00ean t\u1ed1t nh\u1ea5t, xin vui l\u00f2ng li\u00ean h\u1ec7 v\u1edbi Shining Home &#8211; Gia \u0111\u00ecnh Anh Ng\u1eef qua 1900 63 60 52. Ho\u1eb7c \u0111\u1ec3 l\u1ea1i th\u00f4ng tin ngay t\u1ea1i \u0111\u00e2y \u0111\u1ec3 nh\u1eadn \u0111\u01b0\u1ee3c nhi\u1ec1u \u01b0u \u0111\u00e3i l\u00ean t\u1edbi 40% v\u00e0 h\u00e0ng ng\u00e0n t\u00e0i li\u1ec7u h\u1ecdc t\u1eadp mi\u1ec5n ph\u00ed.<\/p>\n<p><a href=\"https:\/\/www.youtube.com\/watch?v=7DSJPVHFROS\" target=\"_blank\" rel=\"noopener\">https:\/\/www.youtube.com\/watch?v=7DSJPVHFROS<\/a><\/p>\n<h2 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Ket_luan\"><\/span>K\u1ebft lu\u1eadn<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<\/p>\n<p dir=\"ltr\">Tr\u00ean \u0111\u00e2y l\u00e0 m\u1ed9t b\u1ea3n t\u00f3m t\u1eaft c\u00e1c h\u01b0\u1edbng d\u1eabn v\u1ec1 c\u00e1ch t\u00ecm b\u1ed9i s\u1ed1 chung nh\u1ecf nh\u1ea5t c\u1ee7a 3 s\u1ed1 \u0111\u01a1n gi\u1ea3n. Hy v\u1ecdng, d\u1ef1a tr\u00ean vi\u1ec7c chia s\u1ebb \u1edf tr\u00ean, h\u1ecd ho\u00e0n to\u00e0n c\u00f3 th\u1ec3 \u00e1p d\u1ee5ng \u0111\u1ec3 gi\u1ea3i quy\u1ebft c\u00e1c b\u00e0i t\u1eadp theo c\u00e1ch ch\u00ednh x\u00e1c v\u00e0 hi\u1ec7u qu\u1ea3 nh\u1ea5t.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>C\u00e1ch nh\u1ecf nh\u1ea5t \u0111\u1ec3 t\u00ecm th\u1ea5y T\u01b0\u1edbng 3 -Ti\u00eau ch\u00ed l\u00e0 m\u1ed9t trong nh\u1eefng v\u1ea5n \u0111\u1ec1 l\u1edbp 6 m\u00e0 h\u1ecd s\u1ebd g\u1eb7p ph\u1ea3i. V\u00ec v\u1eady, \u0111\u1ec3 gi\u00fap h\u1ecdc sinh chinh ph\u1ee5c lo\u1ea1i to\u00e1n n\u00e0y m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3, \u0111\u1ea1t \u0111\u01b0\u1ee3c k\u1ebft qu\u1ea3 t\u1ed1t, h\u00e3y \u00e1p d\u1ee5ng c\u00e1c b\u01b0\u1edbc m\u00e0 kh\u1ec9 chia s\u1ebb trong b\u00e0i vi\u1ebft&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[100],"tags":[],"class_list":["post-14913","post","type-post","status-publish","format-standard","hentry","category-kien-thuc"],"_links":{"self":[{"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/posts\/14913","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/comments?post=14913"}],"version-history":[{"count":1,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/posts\/14913\/revisions"}],"predecessor-version":[{"id":17883,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/posts\/14913\/revisions\/17883"}],"wp:attachment":[{"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/media?parent=14913"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/categories?post=14913"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/tags?post=14913"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}