{"id":14259,"date":"2025-06-07T11:49:16","date_gmt":"2025-06-07T04:49:16","guid":{"rendered":"https:\/\/www.ckconitsha.com\/vn\/?p=14259"},"modified":"2025-07-04T11:20:04","modified_gmt":"2025-07-04T04:20:04","slug":"tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an","status":"publish","type":"post","link":"https:\/\/www.ckconitsha.com\/vn\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/","title":{"rendered":"T\u1ea5t t\u1ea7n t\u1eadt ki\u1ebfn th\u1ee9c d\u1ea5u hi\u1ec7u chia h\u1ebft cho 9 &amp; b\u00e0i t\u1eadp chi ti\u1ebft [c\u00f3 \u0111\u00e1p \u00e1n]"},"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\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/#Dinh_nghia_ve_cac_dau_hieu_chia_het_cho_9\" >\u0110\u1ecbnh ngh\u0129a v\u1ec1 c\u00e1c d\u1ea5u hi\u1ec7u chia h\u1ebft cho 9<\/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\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/#Dau_hieu_chia_het_cho_9\" >D\u1ea5u hi\u1ec7u chia h\u1ebft cho 9<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.ckconitsha.com\/vn\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/#So_nao_chia_het_cho_9\" >S\u1ed1 n\u00e0o chia h\u1ebft cho 9?<\/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.ckconitsha.com\/vn\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/#0_Tat_ca_deu_chia_het_cho_9\" >0 T\u1ea5t c\u1ea3 \u0111\u1ec1u chia h\u1ebft cho 9?<\/a><\/li><\/ul><\/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\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/#Tinh_chat_cua_dau_hieu_chia_het_cho_9\" >T\u00ednh ch\u1ea5t c\u1ee7a d\u1ea5u hi\u1ec7u chia h\u1ebft cho 9<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.ckconitsha.com\/vn\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/#Su_chu_y_va_sai_lam_pho_bien_khi_su_dung_cac_dau_hieu_chia_het_cho_9\" >S\u1ef1 ch\u00fa \u00fd v\u00e0 sai l\u1ea7m ph\u1ed5 bi\u1ebfn khi s\u1eed d\u1ee5ng c\u00e1c d\u1ea5u hi\u1ec7u chia h\u1ebft cho 9<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.ckconitsha.com\/vn\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/#Mot_so_loi_pho_bien_khi_lam_bai_tap_ve_nha_la_chia_het_cho_9\" >M\u1ed9t s\u1ed1 l\u1ed7i ph\u1ed5 bi\u1ebfn khi l\u00e0m b\u00e0i t\u1eadp v\u1ec1 nh\u00e0 l\u00e0 chia h\u1ebft cho 9<\/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\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/#Luu_y_ve_so_am_va_0_trong_dau_hieu_chia_cho_9\" >L\u01b0u \u00fd v\u1ec1 s\u1ed1 \u00e2m v\u00e0 0 trong d\u1ea5u hi\u1ec7u chia cho 9<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/www.ckconitsha.com\/vn\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/#Tap_the_duc_co_chu_ky_cua_9\" >T\u1eadp th\u1ec3 d\u1ee5c c\u00f3 ch\u1eef k\u00fd c\u1ee7a 9<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/www.ckconitsha.com\/vn\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/#Tap_the_duc_trong_sach_giao_khoa_cau_tra_loi\" >T\u1eadp th\u1ec3 d\u1ee5c trong s\u00e1ch gi\u00e1o khoa + c\u00e2u tr\u1ea3 l\u1eddi<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/www.ckconitsha.com\/vn\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/#Bai_tap_ung_dung\" >B\u00e0i t\u1eadp \u1ee9ng d\u1ee5ng<\/a><\/li><\/ul><\/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\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/#Bi_quyet_de_hoc_kien_%E2%80%8B%E2%80%8Bthuc_ve_cac_dau_hieu_la_chia_het_cho_9_hieu_qua\" >B\u00ed quy\u1ebft \u0111\u1ec3 h\u1ecdc ki\u1ebfn \u200b\u200bth\u1ee9c v\u1ec1 c\u00e1c d\u1ea5u hi\u1ec7u l\u00e0 chia h\u1ebft cho 9 hi\u1ec7u qu\u1ea3<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/www.ckconitsha.com\/vn\/tat-tan-tat-kien-thuc-dau-hieu-chia-het-cho-9-bai-tap-chi-tiet-co-dap-an\/#Ket_luan\" >K\u1ebft lu\u1eadn<\/a><\/li><\/ul><\/nav><\/div>\n<\/p>\n<p>D\u1ea5u hi\u1ec7u ph\u00e2n chia cho 9 l\u00e0 m\u1ed9t trong nh\u1eefng ki\u1ebfn \u200b\u200bth\u1ee9c quan tr\u1ecdng, kh\u00f4ng ch\u1ec9 \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng trong to\u00e1n h\u1ecdc, l\u00e0m b\u00e0i t\u1eadp v\u1ec1 nh\u00e0, c\u00e1c c\u00e2u h\u1ecfi thi m\u00e0 c\u00f2n trong th\u1ef1c t\u1ebf. V\u00ec v\u1eady, \u0111\u1ec3 hi\u1ec3u r\u00f5 h\u01a1n v\u1ec1 c\u00e1c quy t\u1eafc khi gi\u1ea3i c\u00e1c b\u00e0i t\u1eadp v\u1edbi c\u00e1c d\u1ea5u hi\u1ec7u ph\u00e2n chia cho 9, h\u00e3y \u0111\u1ec3 Kh\u1ec9 kh\u00e1m ph\u00e1 r\u00f5 r\u00e0ng h\u01a1n trong b\u00e0i vi\u1ebft sau.<\/p>\n<p>                        Xem t\u1ea5t c\u1ea3<\/p>\n<h2 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Dinh_nghia_ve_cac_dau_hieu_chia_het_cho_9\"><\/span>\u0110\u1ecbnh ngh\u0129a v\u1ec1 c\u00e1c d\u1ea5u hi\u1ec7u chia h\u1ebft cho 9<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p dir=\"ltr\">\u0110\u1ec3 gi\u1ea3i quy\u1ebft m\u1ed9t s\u1ed1 b\u00e0i t\u1eadp nh\u1ea5t \u0111\u1ecbnh, hi\u1ec3u kh\u00e1i ni\u1ec7m l\u00e0 r\u1ea5t quan tr\u1ecdng. \u1ede \u0111\u00e2y, d\u1ea5u hi\u1ec7u chia h\u1ebft c\u1ee7a 9 l\u00e0 vi\u1ec7c x\u00e1c \u0111\u1ecbnh m\u1ed9t s\u1ed1 \u0111\u00e3 \u0111\u01b0\u1ee3c \u0111\u01b0a ra c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c chia cho 9 ho\u1eb7c kh\u00f4ng d\u1ef1a tr\u00ean c\u00e1c d\u1ea5u hi\u1ec7u nh\u1eadn th\u1ee9c. V\u00ec v\u1eady, m\u1ed9t s\u1ed1 t\u1ef1 nhi\u00ean l\u00e0 chia h\u1ebft cho 9, c\u00f3 ngh\u0129a l\u00e0 khi chia s\u1ed1 \u0111\u00f3 cho 9, kh\u00f4ng c\u00f3 s\u1ed1 d\u01b0 (s\u1ed1 d\u01b0 l\u00e0 0).<\/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\/dau-hieu-chia-het-cho-9-1.jpg\" alt=\"L\u00e0 d\u1ea5u hi\u1ec7u c\u1ee7a m\u1ed9t danh t\u00ednh l\u00e0 chia h\u1ebft cho 9 hay kh\u00f4ng? (\u1ea2nh: B\u1ed9 s\u01b0u t\u1eadp Internet)\" width=\"100%\"><\/p>\n<h2 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Dau_hieu_chia_het_cho_9\"><\/span>D\u1ea5u hi\u1ec7u chia h\u1ebft cho 9<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p dir=\"ltr\">\u0110\u1ec3 x\u00e1c \u0111\u1ecbnh s\u1ed1 n\u00e0o chia h\u1ebft cho 9, ch\u00fang t\u00f4i d\u1ef1a v\u00e0o c\u00e1c \u0111\u1eb7c \u0111i\u1ec3m sau:<\/p>\n<h3 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"So_nao_chia_het_cho_9\"><\/span>S\u1ed1 n\u00e0o chia h\u1ebft cho 9?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p dir=\"ltr\">\u0110\u1ec3 bi\u1ebft s\u1ed1 n\u00e0o chia h\u1ebft cho 9, \u0111\u00f3 l\u00e0 nh\u1eefng con s\u1ed1 c\u00f3 t\u1ed5ng c\u1ee7a c\u00e1c ch\u1eef s\u1ed1 \u0111\u00f3 c\u00f3 th\u1ec3 chia h\u1ebft cho 9.<\/p>\n<p dir=\"ltr\">* L\u01b0u \u00fd: C\u00e1c s\u1ed1 c\u00f3 t\u1ed5ng c\u1ee7a c\u00e1c ch\u1eef s\u1ed1 kh\u00f4ng chia h\u1ebft cho 9, ch\u00fang kh\u00f4ng chia h\u1ebft cho 9. Ho\u1eb7c n\u1ebfu t\u1ed5ng c\u1ee7a c\u00e1c ch\u1eef s\u1ed1 c\u1ee7a m\u1ed9t s\u1ed1 nh\u1ea5t \u0111\u1ecbnh \u0111\u01b0\u1ee3c chia cho 9 nh\u01b0ng s\u1ed1 l\u01b0\u1ee3ng c\u00f2n l\u1ea1i l\u00e0 s\u1ed1 d\u01b0 v\u00e0 kh\u00f4ng \u0111\u01b0\u1ee3c chia cho 9.<\/p>\n<p dir=\"ltr\"><em>V\u00ed d\u1ee5: <\/em><\/p>\n<p dir=\"ltr\"><em>63: 9 = 7. Ch\u00fang ta c\u00f3: 6 + 3 = 9; 9: 9 = 1<\/em><\/p>\n<p dir=\"ltr\"><em>89: 9 = 9 d\u01b0 8. Ch\u00fang ta c\u00f3: 8+9 = 17; 17: 9 = 1 th\u1eeba 8<\/em><\/p>\n<p dir=\"ltr\">Ngo\u00e0i ra, \u0111\u1ec3 bi\u1ebft li\u1ec7u m\u1ed9t s\u1ed1 t\u1ef1 nhi\u00ean c\u00f3 chia h\u1ebft cho 9 hay kh\u00f4ng, ch\u00fang ta c\u00f3 th\u1ec3 th\u1ef1c hi\u1ec7n ph\u00e2n chia s\u1ed1 \u0111\u00f3 th\u00e0nh 9 v\u00e0 xem c\u00f3 d\u01b0 th\u1eeba hay kh\u00f4ng. N\u1ebfu k\u1ebft qu\u1ea3 kh\u00f4ng c\u00f2n s\u00f3t l\u1ea1i, s\u1ed1 l\u01b0\u1ee3ng l\u00e0 chia h\u1ebft cho 9, trong khi n\u1ebfu k\u1ebft qu\u1ea3 c\u00e2n b\u1eb1ng kh\u00f4ng ph\u1ea3i l\u00e0 0, s\u1ed1 kh\u00f4ng chia cho 9. <em>V\u00ed d\u1ee5: 27 \u0111\u01b0\u1ee3c chia cho 9 v\u00ec 27 % 9 = 0.<\/em><\/p>\n<h3 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"0_Tat_ca_deu_chia_het_cho_9\"><\/span>0 T\u1ea5t c\u1ea3 \u0111\u1ec1u chia h\u1ebft cho 9?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p dir=\"ltr\">Trong to\u00e1n h\u1ecdc, 0 l\u00e0 m\u1ed9t s\u1ed1 chia cho t\u1ea5t c\u1ea3 c\u00e1c s\u1ed1 kh\u00e1c ho\u1eb7c t\u1ea5t c\u1ea3 c\u00e1c s\u1ed1 nguy\u00ean \u0111\u1ec1u chia h\u1ebft cho 1 v\u00e0 s\u1ed1 nguy\u00ean kh\u00e1c c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c chia cho ch\u00ednh n\u00f3. V\u00ec v\u1eady, 0 c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c chia cho 9.<\/p>\n<h2 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Tinh_chat_cua_dau_hieu_chia_het_cho_9\"><\/span>T\u00ednh ch\u1ea5t c\u1ee7a d\u1ea5u hi\u1ec7u chia h\u1ebft cho 9<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p dir=\"ltr\">Tr\u00ean th\u1ef1c t\u1ebf, c\u00e1c d\u1ea5u hi\u1ec7u ph\u00e2n chia \u0111\u1ec1u chia h\u1ebft cho 3 v\u00e0 9 v\u1edbi c\u00e1c li\u00ean h\u1ec7 ch\u1eb7t ch\u1ebd. C\u1ee5 th\u1ec3, m\u1ed9t s\u1ed1 chia t\u1ef1 nhi\u00ean cho 9 ch\u1eafc ch\u1eafn s\u1ebd \u0111\u01b0\u1ee3c chia cho 3.<\/p>\n<p dir=\"ltr\">\u0110\u1ec3 hi\u1ec3u li\u00ean h\u1ec7 n\u00e0y, m\u1ecdi ng\u01b0\u1eddi c\u1ea7n hi\u1ec3u quy t\u1eafc c\u01a1 b\u1ea3n c\u1ee7a b\u1ed9 ph\u1eadn. C\u1ee5 th\u1ec3, khi m\u1ed9t s\u1ed1 t\u1ef1 nhi\u00ean \u0111\u01b0\u1ee3c chia cho 9, c\u00f3 ngh\u0129a l\u00e0 ch\u00fang \u0111\u01b0\u1ee3c bi\u1ec3u di\u1ec5n d\u01b0\u1edbi d\u1ea1ng &#8220;9n&#8221;, trong \u0111\u00f3 n l\u00e0 m\u1ed9t s\u1ed1 nguy\u00ean d\u01b0\u01a1ng. <em>V\u00ed d\u1ee5: 9, 18, 27, 36, 45, 54, &#8230; \u0111\u1ec1u \u0111\u01b0\u1ee3c chia cho 9.<\/em><\/p>\n<p dir=\"ltr\">Tuy nhi\u00ean, n\u1ebfu ng\u01b0\u1ee3c l\u1ea1i, m\u1ed9t s\u1ed1 t\u1ef1 nhi\u00ean \u0111\u01b0\u1ee3c chia cho 3, n\u00f3 kh\u00f4ng nh\u1ea5t thi\u1ebft c\u00f3 th\u1ec3 chia cho 9. <em>V\u00ed d\u1ee5: 3, 6, 9, 12, 15, &#8230; \u0111\u1ec1u \u0111\u01b0\u1ee3c chia cho 3, nh\u01b0ng ch\u1ec9 9 chia cho c\u1ea3 3 v\u00e0 9.<\/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\/dau-hieu-chia-het-cho-9-2.jpg\" alt=\"C\u1ea7n hi\u1ec3u c\u00e1c d\u1ea5u hi\u1ec7u v\u00e0 thu\u1ed9c t\u00ednh c\u1ee7a m\u1ed9t s\u1ed1 chia h\u1ebft cho 9. (\u1ea2nh: Internet s\u01b0u t\u1ea7m)\" width=\"100%\"><\/p>\n<h2 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Su_chu_y_va_sai_lam_pho_bien_khi_su_dung_cac_dau_hieu_chia_het_cho_9\"><\/span>S\u1ef1 ch\u00fa \u00fd v\u00e0 sai l\u1ea7m ph\u1ed5 bi\u1ebfn khi s\u1eed d\u1ee5ng c\u00e1c d\u1ea5u hi\u1ec7u chia h\u1ebft cho 9<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p dir=\"ltr\">Trong qu\u00e1 tr\u00ecnh gi\u1ea3i quy\u1ebft c\u00e1c d\u1ea5u hi\u1ec7u chia h\u1ebft cho 9, m\u1ecdi ng\u01b0\u1eddi c\u1ea7n bi\u1ebft m\u1ed9t s\u1ed1 ghi ch\u00fa sau \u0111\u00e2y:<\/p>\n<h3 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Mot_so_loi_pho_bien_khi_lam_bai_tap_ve_nha_la_chia_het_cho_9\"><\/span>M\u1ed9t s\u1ed1 l\u1ed7i ph\u1ed5 bi\u1ebfn khi l\u00e0m b\u00e0i t\u1eadp v\u1ec1 nh\u00e0 l\u00e0 chia h\u1ebft cho 9<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<ul>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">L\u1ed7i t\u00ednh to\u00e1n t\u1ed5ng c\u00e1c ch\u1eef s\u1ed1: Khi d\u1ef1a v\u00e0o c\u00e1c d\u1ea5u hi\u1ec7u t\u00ednh to\u00e1n t\u1ed5ng c\u1ee7a c\u00e1c s\u1ed1 \u0111\u1ec3 xem n\u00f3 c\u00f3 chia h\u1ebft cho 9 hay kh\u00f4ng, nhi\u1ec1u em b\u00e9 \u0111\u01b0\u1ee3c t\u00ednh cho t\u1ed5ng, do \u0111\u00f3 n\u00f3 d\u1eabn \u0111\u1ebfn k\u1ebft qu\u1ea3 sai. V\u00ec v\u1eady, sau m\u1ed7i k\u1ebft qu\u1ea3, c\u1ea7n ki\u1ec3m tra t\u1ed5ng s\u1ed1 ch\u1eef s\u1ed1 \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o \u0111\u1ed9 ch\u00ednh x\u00e1c.<\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">L\u1ed7i x\u00e1c \u0111\u1ecbnh s\u1ed1 chia cho 9: Nhi\u1ec1u em b\u00e9 c\u00f3 th\u1ec3 nh\u1ea7m l\u1eabn kh\u00ed \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh s\u1ed1 chia cho 9, l\u00e0 s\u1ed1 t\u1ef1 nhi\u00ean v\u1edbi t\u1ed5ng s\u1ed1 ch\u1eef s\u1ed1 chia h\u1ebft cho 9. Nh\u01b0ng n\u1ebfu x\u00e1c \u0111\u1ecbnh l\u1ed7i chia h\u1ebft n\u00e0y, k\u1ebft qu\u1ea3 s\u1ebd sai.<\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">Kh\u00f4ng ki\u1ec3m tra t\u1ea5t c\u1ea3 \u0111\u1ebfn 9 m\u1ed9t c\u00e1ch to\u00e0n di\u1ec7n: M\u1ed9t s\u1ed1 tr\u1ebb th\u1ef1c hi\u1ec7n b\u00e0i t\u1eadp ch\u1ec9 ki\u1ec3m tra s\u1ed1 chia cho 9 s\u1ed1 cu\u1ed1i c\u00f9ng trong chu\u1ed7i m\u00e0 kh\u00f4ng ki\u1ec3m tra t\u1ea5t c\u1ea3 c\u00e1c ch\u1eef s\u1ed1. \u0110i\u1ec1u n\u00e0y r\u1ea5t d\u1ec5 \u0111\u1ec3 x\u00f3a s\u1ed1 s\u1ed1 kh\u00f4ng chia h\u1ebft cho 9 trong chu\u1ed7i d\u1eabn \u0111\u1ebfn k\u1ebft qu\u1ea3 sai<\/p>\n<\/li>\n<\/ul>\n<h3 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Luu_y_ve_so_am_va_0_trong_dau_hieu_chia_cho_9\"><\/span>L\u01b0u \u00fd v\u1ec1 s\u1ed1 \u00e2m v\u00e0 0 trong d\u1ea5u hi\u1ec7u chia cho 9<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p dir=\"ltr\">Trong qu\u00e1 tr\u00ecnh gi\u1ea3i c\u00e1c b\u00e0i t\u1eadp chia cho 9, m\u1ed9t t\u00ednh n\u0103ng \u0111\u1eb7c bi\u1ec7t c\u1ea7n l\u01b0u \u00fd l\u00e0 s\u1ed1 \u00e2m v\u00e0 0 nh\u01b0 sau:<\/p>\n<ul>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">S\u1ed1 \u00e2m: D\u1ea5u hi\u1ec7u chia cho 9 v\u1eabn c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng cho c\u00e1c s\u1ed1 \u00e2m. \u1ede \u0111\u00e2y, n\u1ebfu m\u1ed9t s\u1ed1 \u00e2m thanh chia h\u1ebft cho 9, s\u1ed1 d\u01b0\u01a1ng t\u00ednh c\u1ee7a n\u00f3 v\u1eabn s\u1ebd \u0111\u01b0\u1ee3c chia cho 9. V\u00ed d\u1ee5: -27 l\u00e0 s\u1ed1 \u00e2m v\u00e0 (-27) % 9 = 0, do \u0111\u00f3 s\u1ed1 \u00e2m -27 l\u00e0 chia h\u1ebft cho 9. T\u01b0\u01a1ng t\u1ef1, | 27 | = 27 chia cho 9.<\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">S\u1ed1 0: S\u1ed1 0 l\u00e0 chia h\u1ebft cho t\u1ea5t c\u1ea3 c\u00e1c s\u1ed1, bao g\u1ed3m 9. \u200b\u200bDo \u0111\u00f3, s\u1ed1 0 \u0111\u01b0\u1ee3c chia cho 9. V\u00ed d\u1ee5: 0 % 9 = 0, do \u0111\u00f3 s\u1ed1 0 l\u00e0 chia h\u1ebft cho 9.<\/p>\n<\/li>\n<\/ul>\n<table style=\"border-collapse: collapse;width: 100%;background-color: #c2e0f4\" border=\"1\">\n<tr>\n<td style=\"width: 98.5189%\">\n<p style=\"text-align: center\">Gi\u00fap con b\u1ea1n h\u1ecdc to\u00e1n k\u1ebft h\u1ee3p v\u1edbi ti\u1ebfng Anh si\u00eau ti\u1ebft ki\u1ec7m ch\u1ec9 tr\u00ean \u1ee9ng d\u1ee5ng to\u00e1n h\u1ecdc kh\u1ec9. V\u1edbi n\u1ed9i dung gi\u1ea3ng d\u1ea1y v\u1ea1n n\u0103ng \u0111\u1ec3 gi\u00fap tr\u1ebb ph\u00e1t tri\u1ec3n t\u01b0 duy n\u00e3o b\u1ed9 v\u00e0 ng\u00f4n ng\u1eef to\u00e0n di\u1ec7n ch\u1ec9 v\u1edbi kho\u1ea3ng 2k\/ng\u00e0y.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" style=\"margin-left: auto;margin-right: auto\" class=\"lazyload\" src=\"https:\/\/external-content.duckduckgo.com\/iu\/?u=https:\/\/vnmedia.monkeyuni.net\/upload\/web\/img\/nhantuvanmienphi.png\" alt=\"\" width=\"200\" height=\"39\"><\/p>\n<\/td>\n<\/tr>\n<\/table>\n<h2 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Tap_the_duc_co_chu_ky_cua_9\"><\/span>T\u1eadp th\u1ec3 d\u1ee5c c\u00f3 ch\u1eef k\u00fd c\u1ee7a 9<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p dir=\"ltr\">D\u1ef1a tr\u00ean c\u00e1c quy t\u1eafc v\u00e0 d\u1ea5u hi\u1ec7u tr\u00ean, kh\u1ec9 s\u1ebd t\u00f3m t\u1eaft m\u1ed9t s\u1ed1 b\u00e0i t\u1eadp li\u00ean quan \u0111\u1ec3 ch\u00fang c\u00f3 th\u1ec3 tham kh\u1ea3o v\u00e0 \u00e1p d\u1ee5ng:<\/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\/dau-hieu-chia-het-cho-9-3.jpg\" alt=\"N\u00ean th\u1ef1c h\u00e0nh, gi\u1ea3i quy\u1ebft c\u00e1c b\u00e0i t\u1eadp \u0111\u1ec3 t\u00ecm t\u1ea5t c\u1ea3 chia h\u1ebft cho 9 ng\u01b0\u1eddi th\u01b0\u1eddng xuy\u00ean. (\u1ea2nh: B\u1ed9 s\u01b0u t\u1eadp Internet)\" width=\"100%\"><\/p>\n<h3 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Tap_the_duc_trong_sach_giao_khoa_cau_tra_loi\"><\/span>T\u1eadp th\u1ec3 d\u1ee5c trong s\u00e1ch gi\u00e1o khoa + c\u00e2u tr\u1ea3 l\u1eddi<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p dir=\"ltr\">Gi\u1ea3i th\u01b0\u1edfng \u1edf l\u1edbp 4 Trang 97 B\u00e0i 1: Trong c\u00e1c s\u1ed1 sau, s\u1ed1 n\u00e0o chia h\u1ebft cho 9?<\/p>\n<p dir=\"ltr\">99; 1999; 108; 5643; 29 385.<\/p>\n<p dir=\"ltr\">Gi\u1ea3i ph\u00e1p:<\/p>\n<p dir=\"ltr\">+) S\u1ed1 96 c\u00f3 t\u1ed5ng s\u1ed1 9 + 6 = 15.<\/p>\n<p dir=\"ltr\">Nh\u01b0ng 15 kh\u00f4ng chia h\u1ebft cho 9, v\u00ec v\u1eady s\u1ed1 96 kh\u00f4ng chia h\u1ebft cho 9 (\u0111\u01b0\u1ee3c ch\u1ecdn)<\/p>\n<p dir=\"ltr\">+) S\u1ed1 108 c\u00f3 t\u1ed5ng s\u1ed1 1 + 0 + 8 = 9.<\/p>\n<p dir=\"ltr\">      Nh\u01b0ng 9 l\u00e0 chia h\u1ebft cho 9, v\u00ec v\u1eady s\u1ed1 108 chia h\u1ebft cho 9 (c\u00e1c lo\u1ea1i)<\/p>\n<p dir=\"ltr\">L\u00e0m t\u01b0\u01a1ng t\u1ef1 v\u1edbi ph\u1ea7n c\u00f2n l\u1ea1i.<\/p>\n<p dir=\"ltr\">V\u00ec v\u1eady, trong c\u00e1c s\u1ed1 \u0111\u00e3 cho, c\u00e1c s\u1ed1 kh\u00f4ng chia h\u1ebft cho 9:<\/p>\n<p dir=\"ltr\">96; 7853; 5554; 1097<\/p>\n<p dir=\"ltr\">Gi\u1ea3i th\u01b0\u1edfng \u1edf l\u1edbp 4 Trang 97 B\u00e0i 3: Vi\u1ebft hai s\u1ed1 v\u1edbi ba ch\u1eef s\u1ed1 v\u00e0 chia h\u1ebft cho 9.<\/p>\n<p dir=\"ltr\">Gi\u1ea3i ph\u00e1p:<\/p>\n<p dir=\"ltr\">H\u01b0\u1edbng d\u1eabn: Ch\u1ecdn c\u00e1c ch\u1eef s\u1ed1 ba ch\u1eef s\u1ed1 c\u1ee7a 9 (ho\u1eb7c 18 ho\u1eb7c 27) v\u00e0 sau \u0111\u00f3 k\u1ebft h\u1ee3p n\u00f3 th\u00e0nh m\u1ed9t s\u1ed1.<\/p>\n<p dir=\"ltr\">V\u00ed d\u1ee5: 2 + 3 + 4 = 9. V\u00ec v\u1eady, ch\u00fang t\u00f4i c\u00f3 hai s\u1ed1: 234; 432.<\/p>\n<p dir=\"ltr\">Ngo\u00e0i ra, c\u00f3 nhi\u1ec1u v\u0103n b\u1ea3n kh\u00e1c.<\/p>\n<p dir=\"ltr\">Gi\u1ea3i quy\u1ebft L\u1edbp 4 Trang 97 B\u00e0i 4: T\u00ecm ch\u1eef s\u1ed1 th\u00edch h\u1ee3p v\u00e0o h\u1ed9p \u0111\u1ec3 l\u1ea5y s\u1ed1 chia cho 9: 31 &#8230;; &#8230; 35; 2 &#8230; 5.<\/p>\n<p dir=\"ltr\">Gi\u1ea3i ph\u00e1p:<\/p>\n<p dir=\"ltr\">Gi\u1ea3 s\u1eed ch\u1eef s\u1ed1 \u0111\u1ec3 \u0111i\u1ec1n v\u00e0o h\u1ed9p tr\u1ed1ng l\u00e0 x.<\/p>\n<p dir=\"ltr\">+) \u0110\u1ec3 31x \u0111\u01b0\u1ee3c chia cho 9, t\u1ed5ng c\u1ee7a c\u00e1c ch\u1eef s\u1ed1 chia h\u1ebft cho 9 ho\u1eb7c 3 + 1 + x = 4 + x chia cho 9.<\/p>\n<p dir=\"ltr\">Do \u0111\u00f3 x = 5.<\/p>\n<p dir=\"ltr\">+) \u0110\u1ec3 s\u1ed1 x35 \u0111\u01b0\u1ee3c chia cho 9, t\u1ed5ng c\u1ee7a c\u00e1c ch\u1eef s\u1ed1 chia h\u1ebft cho 9 ho\u1eb7c x + 3 + 5 = x + 8 chia h\u1ebft cho 9.<\/p>\n<p dir=\"ltr\">Do \u0111\u00f3 x = 1<\/p>\n<p dir=\"ltr\">+) \u0110\u1ec3 2&#215;5 \u0111\u01b0\u1ee3c chia cho 9, t\u1ed5ng c\u1ee7a c\u00e1c ch\u1eef s\u1ed1 chia h\u1ebft cho 9 ho\u1eb7c 2 + x + 5 = 7 + x chia cho 9.<\/p>\n<p dir=\"ltr\">Do \u0111\u00f3 x = 2<\/p>\n<p dir=\"ltr\">Ch\u00fang t\u00f4i c\u00f3 k\u1ebft qu\u1ea3 sau: 315; 135; 225<\/p>\n<h3 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Bai_tap_ung_dung\"><\/span>B\u00e0i t\u1eadp \u1ee9ng d\u1ee5ng<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p dir=\"ltr\">B\u00e0i 1: Trong s\u1ed1 c\u00e1c s\u1ed1 1235, 690, 108, 192, 720, 492. T\u00ecm: T\u00ecm ki\u1ebfm:<\/p>\n<p dir=\"ltr\">a) C\u00e1c con s\u1ed1 chia h\u1ebft cho 9.<\/p>\n<p dir=\"ltr\">b) C\u00e1c con s\u1ed1 kh\u00f4ng chia h\u1ebft cho 9.<\/p>\n<p dir=\"ltr\">B\u00e0i 2: T\u00ecm ch\u1eef s\u1ed1 th\u00edch h\u1ee3p \u0111\u1ec3 \u0111i\u1ec1n v\u00e0o * d\u1ea5u hi\u1ec7u cho th\u1ea5y s\u1ed1 145 * l\u00e0 s\u1ed1 chia cho 9.<\/p>\n<p dir=\"ltr\">B\u00e0i 3:<\/p>\n<p dir=\"ltr\">A) C\u00f3 bao nhi\u00eau s\u1ed1 l\u00e0 9 \u0111\u1ebfn 200 nh\u01b0ng chia h\u1ebft cho 9?<\/p>\n<p dir=\"ltr\">b) C\u00f3 bao nhi\u00eau s\u1ed1 kh\u00f4ng chia cho 250 th\u00e0nh 300?<\/p>\n<p dir=\"ltr\">B\u00e0i 4: \u0110\u01b0a ra c\u00e1c s\u1ed1 sau: 92; 108; 135; 206; 277; 423; 1058; 2401. Trong s\u1ed1 nh\u1eefng con s\u1ed1 \u0111\u00f3 c\u00f3 bao nhi\u00eau con s\u1ed1 chia h\u1ebft cho 9?<\/p>\n<p dir=\"ltr\">B\u00e0i 5: T\u1eeb b\u1ed1n ch\u1eef s\u1ed1 0; 1; 3; 5 C\u00f3 bao nhi\u00eau s\u1ed1 c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c vi\u1ebft v\u1edbi ba ch\u1eef s\u1ed1 kh\u00e1c nhau v\u00e0 chia h\u1ebft cho 9?<\/p>\n<p dir=\"ltr\">B\u00e0i 6: V\u1edbi b\u1ed1n ch\u1eef s\u1ed1 0; 1; 4; 5 Vi\u1ebft t\u1ea5t c\u1ea3 s\u1ed1 ba ch\u1eef s\u1ed1 kh\u00e1c nhau v\u1eeba \u0111\u01b0\u1ee3c chia cho 5 v\u00e0 chia h\u1ebft cho 9?<\/p>\n<p dir=\"ltr\">B\u00e0i 7: T\u00ecm m\u1ed9t \u0111\u1ec3 s\u1ed1 2A65 chia h\u1ebft cho 9.<\/p>\n<p dir=\"ltr\">B\u00e0i 8: Cho c\u00e1c con s\u1ed1: 3564; 4352; 6531; 6570; 1248.<\/p>\n<p dir=\"ltr\">a) Vi\u1ebft m\u1ed9t t\u1eadp h\u1ee3p c\u00e1c s\u1ed1 chia chia cho 3 s\u1ed1 tr\u00ean.<\/p>\n<p dir=\"ltr\">b) Vi\u1ebft m\u1ed9t t\u1eadp h\u1ee3p c\u00e1c s\u1ed1 B chia cho 9 trong s\u1ed1 c\u00e1c s\u1ed1 tr\u00ean.<\/p>\n<p dir=\"ltr\">c) S\u1eed d\u1ee5ng k\u00fd hi\u1ec7u \u2282 \u0111\u1ec3 hi\u1ec3n th\u1ecb m\u1ed1i quan h\u1ec7 gi\u1eefa hai b\u1ed9 A v\u00e0 B.<\/p>\n<p dir=\"ltr\">B\u00e0i 9: Xem x\u00e9t c\u00e1c s\u1ea3n ph\u1ea9m sau \u0111\u00e2y l\u00e0 chia h\u1ebft cho 9 No:<\/p>\n<table style=\"border-collapse: collapse;width: 100%\">\n<tr>\n<td>\n<p dir=\"ltr\">a) 396. 11<\/p>\n<\/td>\n<td>\n<p dir=\"ltr\">b) 2. 4. 6. &#8230;&#8230; 12<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td>\n<p dir=\"ltr\">c) 38. 127. 26<\/p>\n<\/td>\n<td>\n<p dir=\"ltr\">d) 1. 3. 5. 7<\/p>\n<\/td>\n<\/tr>\n<\/table>\n<p dir=\"ltr\">B\u00e0i h\u1ecdc 10:<\/p>\n<p dir=\"ltr\">a) T\u00ecm s\u1ed1 t\u1ef1 nhi\u00ean x bi\u1ebft x chia cho 9 v\u00e0 x &lt;80.<\/p>\n<p dir=\"ltr\">b) s\u1ed1 3 -digit nh\u1ecf h\u01a1n 150 v\u00e0 chia h\u1ebft cho 9<\/p>\n<p dir=\"ltr\">B\u00e0i 11: T\u00ecm 1 s\u1ed1 v\u1edbi 2 ch\u1eef s\u1ed1 bi\u1ebft r\u1eb1ng s\u1ed1 chia 2 d\u01b0 th\u1eeba 1, chia 5 d\u01b0 l\u01b0\u1ee3ng 2 v\u00e0 chia t\u1ea5t c\u1ea3 ch\u00fang cho 9<\/p>\n<p dir=\"ltr\">B\u00e0i 12: LAN n\u00f3i: &#8220;Nh\u1eefng con s\u1ed1 c\u00f3 t\u1ed5ng s\u1ed1 ch\u1eef s\u1ed1 kh\u00f4ng chia h\u1ebft cho 9, ch\u00fang kh\u00f4ng chia h\u1ebft cho 9&#8221;. Theo b\u1ea1n, LAN l\u00e0 \u0111\u00fang hay sai?<\/p>\n<p dir=\"ltr\">B\u00e0i h\u1ecdc 13: \u0110\u01b0a ra c\u00e1c s\u1ed1 sau: 92; 108; 135; 206; 277; 423; 1058; 2401. C\u00f3 bao nhi\u00eau con s\u1ed1 chia h\u1ebft cho 9?<\/p>\n<p dir=\"ltr\">B\u00e0i h\u1ecdc 14: \u0110i\u1ec1n v\u00e0o s\u1ed1 th\u00edch h\u1ee3p v\u00e0o d\u1ea5u h\u1ecfi:<\/p>\n<p dir=\"ltr\">Bi\u1ebft 3021<\/p>\n<p dir=\"ltr\">B\u00e0i h\u1ecdc 15: C\u1eeda h\u00e0ng h\u00e0ng ng\u00e0y \u0111\u1ea7u ti\u00ean b\u00e1n \u00edt h\u01a1n 75m \u0111\u1ed3ng h\u1ed3 nh\u01b0ng h\u01a1n 70m. Bi\u1ebft s\u1ed1 m\u00e9t c\u1ee7a ng\u00e0y \u0111\u1ea7u ti\u00ean \u0111\u01b0\u1ee3c b\u00e1n \u0111\u01b0\u1ee3c chia cho 9. Ng\u00e0y th\u1ee9 hai c\u1eeda h\u00e0ng b\u00e1n s\u1ed1 m\u00e9t v\u1ea3i hai l\u1ea7n s\u1ed1 l\u01b0\u1ee3ng v\u1ea3i \u0111\u01b0\u1ee3c b\u00e1n v\u00e0o ng\u00e0y \u0111\u1ea7u ti\u00ean.<\/p>\n<p dir=\"ltr\">V\u00ec v\u1eady, c\u00f3 bao nhi\u00eau m\u00e9t c\u1ee7a c\u1eeda h\u00e0ng b\u00e1n.<\/p>\n<p dir=\"ltr\">\n<h2 dir=\"ltr\"><span class=\"ez-toc-section\" id=\"Bi_quyet_de_hoc_kien_%E2%80%8B%E2%80%8Bthuc_ve_cac_dau_hieu_la_chia_het_cho_9_hieu_qua\"><\/span>B\u00ed quy\u1ebft \u0111\u1ec3 h\u1ecdc ki\u1ebfn \u200b\u200bth\u1ee9c v\u1ec1 c\u00e1c d\u1ea5u hi\u1ec7u l\u00e0 chia h\u1ebft cho 9 hi\u1ec7u qu\u1ea3<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p dir=\"ltr\">\u0110\u1ec3 gi\u00fap h\u1ecd l\u00e0m ch\u1ee7 ki\u1ebfn \u200b\u200bth\u1ee9c khi x\u00e1c \u0111\u1ecbnh s\u1ed1 chia cho 9, \u0111\u00e2y l\u00e0 m\u1ed9t s\u1ed1 m\u1eb9o h\u1eefu \u00edch:<\/p>\n<ul>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">N\u1eafm v\u1eefng c\u00e1c d\u1ea5u hi\u1ec7u ph\u00e2n chia cho 9: S\u1ed1 s\u1ed1 chia h\u1ebft cho 9 l\u00e0 kh\u00e1 \u0111\u01a1n gi\u1ea3n b\u1eb1ng c\u00e1ch t\u00ednh t\u1ed5ng s\u1ed1 s\u1ed1 c\u1ee7a s\u1ed1 \u0111\u00f3 \u0111\u1ec3 xem t\u1ea5t c\u1ea3 \u0111\u1ebfn 9 ho\u1eb7c kh\u00f4ng, con s\u1ed1 chia h\u1ebft cho 9.<\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">Xem x\u00e9t c\u00e1c v\u1ea5n \u0111\u1ec1 th\u1ef1c t\u1ebf: Cha m\u1eb9 c\u00f3 th\u1ec3 l\u1ea5y v\u00ed d\u1ee5 trong th\u1ef1c t\u1ebf nh\u01b0 h\u1ecfi m\u1ed9t lo\u1ea1i ti\u1ec1n t\u1ec7 v\u1edbi con s\u1ed1 n\u00e0y \u0111\u01b0\u1ee3c chia cho 9 ng\u01b0\u1eddi?<\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">Hi\u1ec3u c\u00e1c thu\u1ed9c t\u00ednh c\u00f3 li\u00ean quan: \u0110\u1ec3 gi\u1ea3i quy\u1ebft c\u00e1c b\u00e0i t\u1eadp chia cho 9, ch\u00fang ta n\u00ean bi\u1ebft m\u1ed9t s\u1ed1 t\u00ednh ch\u1ea5t li\u00ean quan h\u01a1n nh\u01b0 b\u1ea3n ch\u1ea5t c\u1ee7a s\u1ea3n ph\u1ea9m, t\u1ed5ng s\u1ed1, th\u01b0\u01a1ng t\u00edch ho\u1eb7c th\u01b0\u01a1ng m\u1ea1i c\u1ee7a b\u1ed9 ph\u1eadn c\u0169ng r\u1ea5t quan tr\u1ecdng.<\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">Th\u1ef1c hi\u1ec7n c\u00e1c b\u00e0i t\u1eadp: M\u1ed9t khi b\u1ea1n \u0111\u00e3 n\u1eafm b\u1eaft \u0111\u01b0\u1ee3c l\u00fd thuy\u1ebft, khuy\u1ebfn kh\u00edch v\u00e0 y\u00eau c\u1ea7u em b\u00e9 th\u1ef1c h\u00e0nh l\u00e0m b\u00e0i t\u1eadp v\u1ec1 nh\u00e0 th\u01b0\u1eddng xuy\u00ean t\u1eeb nhi\u1ec1u ngu\u1ed3n kh\u00e1c nhau b\u00ean c\u1ea1nh s\u00e1ch gi\u00e1o khoa \u0111\u1ec3 c\u1ea3i thi\u1ec7n kh\u1ea3 n\u0103ng t\u00ednh to\u00e1n c\u1ee7a ch\u00fang.<\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\" role=\"presentation\">X\u00e2y d\u1ef1ng m\u1ed9t n\u1ec1n t\u1ea3ng to\u00e1n h\u1ecdc v\u1eefng ch\u1eafc v\u1edbi to\u00e1n h\u1ecdc kh\u1ec9: \u0110\u00e2y l\u00e0 m\u1ed9t \u1ee9ng d\u1ee5ng gi\u1ea3ng d\u1ea1y to\u00e1n h\u1ecdc cho tr\u1ebb m\u1eabu gi\u00e1o v\u00e0 h\u1ecdc sinh ti\u1ec3u h\u1ecdc, nh\u1eefng ng\u01b0\u1eddi \u0111\u01b0\u1ee3c nhi\u1ec1u ph\u1ee5 huynh tin t\u01b0\u1edfng. T\u00ednh n\u0103ng \u0111\u1eb7c bi\u1ec7t c\u1ee7a Shining Home &#8211; Gia \u0111\u00ecnh Anh Ng\u1eef Math l\u00e0 \u00e1p d\u1ee5ng c\u00e1c ph\u01b0\u01a1ng ph\u00e1p gi\u1ea3ng d\u1ea1y t\u00edch c\u1ef1c, \u0111\u1ec3 ch\u00fang c\u00f3 th\u1ec3 ch\u01a1i v\u00e0 h\u1ecdc c\u00e1ch c\u1ea3m th\u1ea5y ph\u1ea5n kh\u00edch v\u00e0 c\u00f3 \u0111\u01b0\u1ee3c ki\u1ebfn \u200b\u200bth\u1ee9c t\u1ed1t h\u01a1n. \u0110\u1ed3ng th\u1eddi, \u1ee9ng d\u1ee5ng c\u0169ng c\u00e1 nh\u00e2n h\u00f3a b\u00e0i h\u1ecdc c\u1ee7a t\u1eebng \u0111\u1ed1i t\u01b0\u1ee3ng, \u0111\u01b0\u1ee3c chia th\u00e0nh nhi\u1ec1u c\u1ea5p \u0111\u1ed9 v\u00e0 s\u1ef1 \u0111a d\u1ea1ng to\u00e1n h\u1ecdc t\u1eeb \u0111\u1ea1i s\u1ed1 sang h\u00ecnh h\u1ecdc \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o em b\u00e9 bi\u1ebft ki\u1ebfn \u200b\u200bth\u1ee9c t\u1ed1t nh\u1ea5t. Do \u0111\u00f3 h\u1ed7 tr\u1ee3 h\u1ecdc t\u1eadp ho\u1eb7c \u1ee9ng d\u1ee5ng th\u1ef1c t\u1ebf.<\/p>\n<\/li>\n<\/ul>\n<p style=\"text-align: center\"><a href=\"https:\/\/www.youtube.com\/watch?v=7DSJPVHFROS\" target=\"_blank\" rel=\"noopener\">https:\/\/www.youtube.com\/watch?v=7DSJPVHFROS<\/a><\/p>\n<p dir=\"ltr\">\u0110\u0103ng k\u00fd ngay \u0111\u1ec3 \u0111\u01b0\u1ee3c t\u01b0 v\u1ea5n mi\u1ec5n ph\u00ed v\u00e0 nh\u1eadn \u0111\u01b0\u1ee3c gi\u1ea3m gi\u00e1 l\u00ean t\u1edbi 40% ph\u1ee5 huynh.<img loading=\"lazy\" decoding=\"async\" style=\"margin-left: auto;margin-right: auto\" class=\"lazyload\" src=\"https:\/\/external-content.duckduckgo.com\/iu\/?u=https:\/\/vnmedia.monkeyuni.net\/upload\/web\/img\/button_dang-ky-ngay-1.png\" alt=\"\" width=\"200\" height=\"27\"><\/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\">V\u1edbi vi\u1ec7c chia s\u1ebb \u1edf tr\u00ean, ng\u01b0\u1eddi ta hy v\u1ecdng s\u1ebd gi\u00fap tr\u1ebb em d\u1ec5 d\u00e0ng chinh ph\u1ee5c c\u00e1c d\u1ea5u hi\u1ec7u chia h\u1ebft cho 9, c\u0169ng nh\u01b0 \u00e1p d\u1ee5ng trong th\u1ef1c t\u1ebf m\u1ed9t c\u00e1ch ch\u00ednh x\u00e1c v\u00e0 hi\u1ec7u qu\u1ea3.<\/p>\n<p>Ngu\u1ed3n: <a href=\"https:\/\/www.ckconitsha.com\/vn\/\">https:\/\/www.ckconitsha.com\/vn\/<\/a> T\u00e1c gi\u1ea3: <a href=\"https:\/\/www.ckconitsha.com\/vn\/author\/nguyenlandung\">Nguy\u1ec5n L\u00e2n d\u0169ng<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>D\u1ea5u hi\u1ec7u ph\u00e2n chia cho 9 l\u00e0 m\u1ed9t trong nh\u1eefng ki\u1ebfn \u200b\u200bth\u1ee9c quan tr\u1ecdng, kh\u00f4ng ch\u1ec9 \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng trong to\u00e1n h\u1ecdc, l\u00e0m b\u00e0i t\u1eadp v\u1ec1 nh\u00e0, c\u00e1c c\u00e2u h\u1ecfi thi m\u00e0 c\u00f2n trong th\u1ef1c t\u1ebf. V\u00ec v\u1eady, \u0111\u1ec3 hi\u1ec3u r\u00f5 h\u01a1n v\u1ec1 c\u00e1c quy t\u1eafc khi gi\u1ea3i c\u00e1c b\u00e0i t\u1eadp v\u1edbi c\u00e1c d\u1ea5u hi\u1ec7u&#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-14259","post","type-post","status-publish","format-standard","hentry","category-kien-thuc"],"_links":{"self":[{"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/posts\/14259","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=14259"}],"version-history":[{"count":2,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/posts\/14259\/revisions"}],"predecessor-version":[{"id":17539,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/posts\/14259\/revisions\/17539"}],"wp:attachment":[{"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/media?parent=14259"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/categories?post=14259"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/tags?post=14259"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}