{"id":2525,"date":"2021-10-14T21:00:39","date_gmt":"2021-10-14T14:00:39","guid":{"rendered":"https:\/\/www.vietlearn.org\/post\/?p=2525"},"modified":"2021-10-14T22:10:26","modified_gmt":"2021-10-14T15:10:26","slug":"cung-be-hoc-toan-tai-teky-bai-12-dau-hieu-chia-het-cho-3-cho-9","status":"publish","type":"post","link":"https:\/\/www.vietlearn.org\/kien-thuc\/cung-be-hoc-toan-tai-teky-bai-12-dau-hieu-chia-het-cho-3-cho-9\/","title":{"rendered":"C\u00f9ng b\u00e9 h\u1ecdc To\u00e1n t\u1ea1i TEKY: B\u00e0i 12 \u2013 D\u1ea5u hi\u1ec7u chia h\u1ebft cho 3, cho 9"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">Ghi ch\u00fa: T\u00e0i li\u1ec7u tr\u00edch d\u1eabn<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Trong bu\u1ed5i h\u1ecdc tr\u01b0\u1edbc, b\u00e9 \u0111\u00e3 \u0111\u01b0\u1ee3c t\u00ecm hi\u1ec3u v\u1ec1 d\u1ea5u hi\u1ec7u chia h\u1ebft cho 2 v\u00e0 5, b\u00e0i vi\u1ebft n\u00e0y, Vietlearn s\u1ebd c\u00f9ng c\u00e1c b\u00e9 kh\u00e1m ph\u00e1 c\u00e1c d\u1ea5u hi\u1ec7u chia h\u1ebft cho 3 v\u00e0 9. B\u1eadt m\u00ed nh\u1ecf l\u00e0 d\u1ea5u hi\u1ec7u chia h\u1ebft cho 3 v\u00e0 9 c\u0169ng d\u1ec5 nh\u01b0 chia h\u1ebft cho 2 v\u00e0 5.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">D\u1ea5u hi\u1ec7u chia h\u1ebft cho 3, cho 9<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>Nh\u1eadn x\u00e9t m\u1edf \u0111\u1ea7u<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">Nh\u1eadn x\u00e9t: M\u1ecdi s\u1ed1 \u0111\u1ec1u vi\u1ebft \u0111\u01b0\u1ee3c d\u01b0\u1edbi d\u1ea1ng t\u1ed5ng c\u00e1c ch\u1eef s\u1ed1 c\u1ee7a n\u00f3 c\u1ed9ng v\u1edbi m\u1ed9t s\u1ed1 chia h\u1ebft cho 9.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">X\u00e9t s\u1ed1 378, ta th\u1ea5y 378 = 3.100 + 7.10 + 8<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Vi\u1ebft 100 th\u00e0nh 99 + 1, 10 th\u00e0nh 9 + 1 (c\u00e1c s\u1ed1 99 v\u00e0 9 \u0111\u1ec1u chia h\u1ebft cho 9)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ta \u0111\u01b0\u1ee3c:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Nh\u01b0 v\u1eady, s\u1ed1 378 vi\u1ebft \u0111\u01b0\u1ee3c d\u01b0\u1edbi d\u1ea1ng t\u1ed5ng c\u00e1c ch\u1eef s\u1ed1 c\u1ee7a n\u00f3 (l\u00e0 3 + 7 + 8) c\u1ed9ng v\u1edbi m\u1ed9t s\u1ed1 chia h\u1ebft cho 9 (l\u00e0 3 . 11 . 9 + 7 . 9).<\/p>\n\n\n\n<ol class=\"wp-block-list\" start=\"2\"><li>D\u1ea5u hi\u1ec7u chia h\u1ebft cho 9<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">Nh\u1eefng s\u1ed1 chia h\u1ebft cho 9 c\u00f3 d\u1ea5u hi\u1ec7u nh\u01b0 th\u1ebf n\u00e0o<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">V\u00ed d\u1ee5: \u00c1p d\u1ee5ng nh\u1eadn x\u00e9t m\u1edf \u0111\u1ea7u, x\u00e9t xem:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">S\u1ed1 341 c\u00f3 chia h\u1ebft cho 9 kh\u00f4ng? S\u1ed1 2124 c\u00f3 chia h\u1ebft cho 9 kh\u00f4ng?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">K\u1ebft lu\u1eadn 1: S\u1ed1 c\u00f3 t\u1ed5ng c\u00e1c ch\u1eef s\u1ed1 chia h\u1ebft cho 9 th\u00ec chia h\u1ebft cho 9.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">2124 = (2 + 1 + 2 + 4) + (S\u1ed1 chia h\u1ebft cho 9)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">=9 + (s\u1ed1 chia h\u1ebft cho 9)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">S\u1ed1 2124 chia h\u1ebft cho 9 c\u1ea3 hai s\u1ed1 h\u1ea1ng \u0111\u1ec1u chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">K\u1ebft lu\u1eadn 2: S\u1ed1 c\u00f3 t\u1ed5ng c\u00e1c ch\u1eef s\u1ed1 kh\u00f4ng chia h\u1ebft cho 9 th\u00ec kh\u00f4ng chia h\u1ebft cho 9.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">341 = (3 + 4 + 1) + (s\u1ed1 chia h\u1ebft cho 9)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">= 8 + (s\u1ed1 chia h\u1ebft cho 9)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">S\u1ed1 341 kh\u00f4ng chia h\u1ebft cho 9 v\u00ec m\u1ed9t s\u1ed1 h\u1ea1ng kh\u00f4ng chia h\u1ebft cho 9, s\u1ed1 h\u1ea1ng c\u00f2n l\u1ea1i chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u00e1c s\u1ed1 c\u00f3 t\u1ed5ng c\u00e1c ch\u1eef s\u1ed1 chia h\u1ebft cho 9 th\u00ec chia h\u1ebft cho 9 v\u00e0 ch\u1ec9 nh\u1eefng s\u1ed1 \u0111\u00f3 m\u1edbi chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">B\u00e0i t\u1eadp: Trong c\u00e1c s\u1ed1 sau, s\u1ed1 n\u00e0o chia h\u1ebft cho 9, s\u1ed1 n\u00e0o kh\u00f4ng chia h\u1ebft cho 9?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">778; 999; 172; 449.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Gi\u1ea3i:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u00e1c s\u1ed1 chia h\u1ebft cho 9 l\u00e0: 999; 172 v\u00ec 999 c\u00f3 t\u1ed5ng l\u00e0 27<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u00e1c s\u1ed1 kh\u00f4ng chia h\u1ebft cho 9 l\u00e0 : 778; 449, 172 v\u00ec 778 c\u00f3 t\u1ed5ng l\u00e0 22, 449 c\u00f3 t\u1ed5ng l\u00e0 17, 172 c\u00f3 t\u1ed5ng l\u00e0 10, c\u00e1c s\u1ed1 n\u00e0y kh\u00f4ng chia h\u1ebft cho 9.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">V\u00ed d\u1ee5 v\u1eadn d\u1ee5ng:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">11 c\u00f3 t\u1ed5ng c\u00e1c ch\u1eef s\u1ed1 l\u00e0 2. S\u1ed1 2 kh\u00f4ng chia h\u1ebft cho 9 n\u00ean 11 kh\u00f4ng chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">63 c\u00f3 t\u1ed5ng c\u00e1c ch\u1eef s\u1ed1 l\u00e0 9. S\u1ed1 9 chia h\u1ebft cho 9 n\u00ean 63 chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">117 c\u00f3 t\u1ed5ng c\u00e1c ch\u1eef s\u1ed1 l\u00e0 9. Do \u0111\u00f3 117 chia h\u1ebft cho 9<\/p>\n\n\n\n<ol class=\"wp-block-list\" start=\"3\"><li>D\u1ea5u hi\u1ec7u chia h\u1ebft cho 3<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">Nh\u1eefng s\u1ed1 chia h\u1ebft cho 3 c\u00f3 d\u1ea5u hi\u1ec7u g\u00ec<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">V\u00ed d\u1ee5: \u00c1p d\u1ee5ng nh\u1eadn x\u00e9t m\u1edf \u0111\u1ea7u, xem x\u00e9t:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">S\u1ed1 3341 c\u00f3 chia h\u1ebft cho 3 kh\u00f4ng? S\u1ed1 1463 c\u00f3 chia h\u1ebft cho 3 kh\u00f4ng?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">K\u1ebft lu\u1eadn 1: S\u1ed1 c\u00f3 t\u1ed5ng c\u00e1c ch\u1eef s\u1ed1 chia h\u1ebft cho 3 th\u00ec chia h\u1ebft cho 3.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">3342 = (3 + 3 + 4 + 2) + (s\u1ed1 chia h\u1ebft cho 9)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">= 11 + (s\u1ed1 chia h\u1ebft cho 9)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">= 11 + (s\u1ed1 chia h\u1ebft cho 3)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">S\u1ed1 2242 chia h\u1ebft cho 3 v\u00ec c\u00e1c s\u1ed1 h\u1ea1ng \u0111\u1ec1u chia h\u1ebft cho 3<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">K\u1ebft lu\u1eadn 2: S\u1ed1 c\u00f3 t\u1ed5ng c\u00e1c ch\u1eef s\u1ed1 kh\u00f4ng chia h\u1ebft cho 3 th\u00ec kh\u00f4ng chia h\u1ebft cho 3.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">1463 = (1 +4 + 6 + 3) + (s\u1ed1 chia h\u1ebft cho 9)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">= 14 + (s\u1ed1 chia h\u1ebft cho 9)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">= 14 + (s\u1ed1 chia h\u1ebft cho 3)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">S\u1ed1 1463 kh\u00f4ng chia h\u1ebft cho 3 v\u00ec m\u1ed9t s\u1ed1 h\u1ea1ng kh\u00f4ng chia h\u1ebft cho 3, s\u1ed1 h\u1ea1ng c\u00f2n l\u1ea1i chia h\u1ebft cho 3.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u00e1c s\u1ed1 c\u00f3 t\u1ed5ng c\u00e1c ch\u1eef s\u1ed1 chia h\u1ebft cho 3 th\u00ec chia h\u1ebft cho 3 v\u00e0 ch\u1ec9 nh\u1eefng s\u1ed1 \u0111\u00f3 m\u1edbi chia h\u1ebft cho 3<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p>T\u1ea3i ngay: B\u1ed9 \u0111\u1ec1 thi v\u00e0 b\u00e0i h\u1ec7 th\u1ed1ng ki\u1ebfn th\u1ee9c m\u00f4n To\u00e1n tuy\u1ec7t hay<\/p><\/blockquote>\n\n\n\n<ol class=\"wp-block-list\" start=\"4\"><li>L\u01b0u \u00fd \u2013 D\u1ea5u hi\u1ec7u nh\u1eadn bi\u1ebft chia h\u1ebft cho 3, cho 9<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">L\u01b0u \u00fd 1: M\u1ecdi s\u1ed1 chia h\u1ebft cho 9 \u0111\u1ec1u chia h\u1ebft cho 3<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">V\u00ed d\u1ee5: 4176 = 4 + 1 + 7 + 6 = 18<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">18 chia h\u1ebft cho c\u1ea3 9 v\u00e0 3<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>       22 140 = 2 + 2 + 1 + 4 + 0 = 9<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">9 chia h\u1ebft cho c\u1ea3 9 v\u00e0 3<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">L\u01b0u \u00fd 2: S\u1ed1 chia h\u1ebft cho 3 c\u00f3 th\u1ec3 kh\u00f4ng chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">V\u00ed d\u1ee5: 271 = 2 + 7 + 1 =15<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">15 chia h\u1ebft cho 3 nh\u01b0ng kh\u00f4ng chia h\u1ebft cho 9<\/p>\n\n\n\n<ol class=\"wp-block-list\" start=\"5\"><li>B\u00e0i t\u1eadp S\u00e1ch gi\u00e1o khoa trang 41<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">B\u00e0i t\u1eadp 101:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">B\u00e0i t\u1eadp 101 s\u00e1ch gi\u00e1o khoa<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">L\u1eddi gi\u1ea3i:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ta c\u00f3:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">187 = 1 + 8 + 7 = 16<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">16 kh\u00f4ng chia h\u1ebft cho 3 c\u0169ng kh\u00f4ng chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">1347 = 1 + 3 + 4 + 7 = 15<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">15 chia h\u1ebft cho 3 nh\u01b0ng kh\u00f4ng chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">2515 = 2 + 5 + 1 + 5 = 12<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">12 chia h\u1ebft cho 3 nh\u01b0ng kh\u00f4ng chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">6534 = 6 + 5 + 3 + 4 = 18<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">18 chia h\u1ebft cho 9 n\u00ean c\u0169ng chia h\u1ebft cho 3<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">93 258 = 9 + 3 + 2 + 5 + 8 = 27<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">27 chia h\u1ebft cho 9 n\u00ean c\u0169ng chia h\u1ebft cho 3<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u0110\u00e1p s\u1ed1: S\u1ed1 chia h\u1ebft cho 3 l\u00e0: 1347, 2515, 6534, 93 258<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>          S\u1ed1 chia h\u1ebft cho 9 l\u00e0: 6534, 93 258<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">B\u00e0i t\u1eadp 102:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">B\u00e0i t\u1eadp 102 s\u00e1ch gi\u00e1o khoa<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">L\u1eddi gi\u1ea3i:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ta c\u00f3:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">3564 = 3 + 5 + 6 + 4 = 18<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">18 chia h\u1ebft cho 9 n\u00ean c\u0169ng chia h\u1ebft cho 3<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">4352 = 4 + 3 + 5 + 2 = 14<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">14 kh\u00f4ng chia h\u1ebft cho 3 c\u0169ng kh\u00f4ng chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">6531 = 6 + 5 + 3 + 1 = 15<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">15 chia h\u1ebft cho 3 nh\u01b0ng kh\u00f4ng chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">6570 = 6 + 5 + 7 + 0 = 18<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">18 chia h\u1ebft cho 9 n\u00ean c\u0169ng chia h\u1ebft cho 3<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">1248 = 1 + 2 + 4 + 8 = 15<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">15 chia h\u1ebft cho 3 nh\u01b0ng kh\u00f4ng chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">=&gt; C\u00e1c s\u1ed1 chia h\u1ebft cho 3: 3564: 6531; 6570; 1248.<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code> C\u00e1c s\u1ed1 chia h\u1ebft cho 9: 3564; 6570.<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">a. T\u1eadp h\u1ee3p c\u00e1c s\u1ed1 chia h\u1ebft cho 3<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A = { 3564: 6531; 6570; 1248}<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">b. T\u1eadp h\u1ee3p c\u00e1c s\u1ed1 chia h\u1ebft cho 9:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">B = {3564; 6570}<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">c. M\u1ed1i quan h\u1ec7 gi\u1eefa t\u1eadp h\u1ee3p A v\u00e0 B: B \u2282 A<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">B\u00e0i t\u1eadp 103:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">B\u00e0i t\u1eadp 103 s\u00e1ch gi\u00e1o khoa<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">L\u1eddi gi\u1ea3i:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">a. Ta c\u00f3:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">1251 + 5316 = 6567<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">6567 = 6 + 5 + 6 + 7 = 24<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">24 chia h\u1ebft cho 3 nh\u01b0ng kh\u00f4ng chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">V\u1eady 1251 + 5316 chia h\u1ebft cho 3 nh\u01b0ng kh\u00f4ng chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">b. Ta c\u00f3:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">5436 \u2013 1324 = 4112<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">4112 = 4 + 1 + 1 + 2 =9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">9 chia h\u1ebft cho c\u1ea3 3 v\u00e0 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">V\u1eady 5436 \u2013 1324 chia h\u1ebft cho 3 v\u00e0 chia h\u1ebft cho 9<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">c. Ta c\u00f3:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">1 . 2 . 3 . 4 . 5 . 6 + 27 = 747<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">747 = 7 + 4 + 7 = 18<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">18 chia h\u1ebft cho 9 n\u00ean c\u0169ng chia h\u1ebft cho 3<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">V\u1eady 1 . 2 . 3 . 4 . 5 . 6 + 27 chia h\u1ebft cho 3 v\u00e0 chia h\u1ebft cho 9.<\/p>\n\n\n\n<ol class=\"wp-block-list\" start=\"6\"><li>B\u00e0i t\u1eadp v\u1eadn d\u1ee5ng d\u1ea5u hi\u1ec7u nh\u1eadn bi\u1ebft chia h\u1ebft cho 3, cho 9<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">B\u00e0i t\u1eadp 1: Trong c\u00e1c s\u1ed1 d\u01b0\u1edbi \u0111\u00e2y s\u1ed1 n\u00e0o chia h\u1ebft cho 3, s\u1ed1 n\u00e0o chia h\u1ebft cho 9 ?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">445; 348; 1458; 4533; 564; 117.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Gi\u1ea3i:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u00e1c s\u1ed1 chia h\u1ebft cho 3 l\u00e0: 348; 1458; 4533; 564; 117.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u00e1c s\u1ed1 chia h\u1ebft cho 9 l\u00e0 : 1458; 117.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">B\u00e0i t\u1eadp 2: D\u00f9ng 3 trong 4 ch\u1eef s\u1ed1 4; 5; 6; 0 h\u00e3y gh\u00e9p th\u00e0nh c\u00e1c s\u1ed1 t\u1ef1 nhi\u00ean c\u00f3 ba ch\u1eef s\u1ed1 sao cho c\u00e1c s\u1ed1 \u0111\u00f3:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Chia h\u1ebft cho 9.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Chia h\u1ebft cho nh\u01b0ng kh\u00f4ng chia h\u1ebft cho 9.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Gi\u1ea3i<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ta gh\u00e9p th\u00e0nh c\u00e1c s\u1ed1 t\u1ef1 nhi\u00ean c\u00f3 ba ch\u1eef s\u1ed1 chia h\u1ebft cho 9 l\u00e0: 450; 405; 504; 540.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ta gh\u00e9p th\u00e0nh c\u00e1c s\u1ed1 t\u1ef1 nhi\u00ean c\u00f3 ba ch\u1eef s\u1ed1 chia h\u1ebft cho 3 m\u00e0 kh\u00f4ng chia h\u1ebft cho 9 l\u00e0: 456; 465; 546; 564; 654; 645.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Kho t\u00e0i li\u1ec7u <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">h\u1ecdc t\u1eadp<\/a> Mi\u1ec5n Ph\u00ed \u2013 Vietlearn<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">N\u1eafm v\u1eefng <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">ki\u1ebfn th\u1ee9c c\u01a1 b\u1ea3n<\/a> v\u1ec1 \u01af\u1edbc chung l\u1edbn nh\u1ea5t<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">K<\/p>\n\n\n\n\n\n\n","protected":false},"excerpt":{"rendered":"<p>Ghi ch\u00fa: T\u00e0i li\u1ec7u tr\u00edch d\u1eabn Trong bu\u1ed5i h\u1ecdc tr\u01b0\u1edbc, b\u00e9 \u0111\u00e3 \u0111\u01b0\u1ee3c t\u00ecm hi\u1ec3u v\u1ec1 d\u1ea5u hi\u1ec7u chia h\u1ebft cho 2 v\u00e0 5, b\u00e0i vi\u1ebft n\u00e0y, Vietlearn s\u1ebd c\u00f9ng c\u00e1c b\u00e9 kh\u00e1m ph\u00e1 c\u00e1c d\u1ea5u hi\u1ec7u chia h\u1ebft cho 3 v\u00e0 9. B\u1eadt m\u00ed nh\u1ecf l\u00e0 d\u1ea5u hi\u1ec7u chia h\u1ebft cho 3 v\u00e0 9 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_disable_autopaging":false},"categories":[3,9],"tags":[],"class_list":["post-2525","post","type-post","status-publish","format-standard","hentry","category-tieu-hoc","category-toan-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/2525","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/comments?post=2525"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/2525\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=2525"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=2525"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=2525"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}