{"id":1081,"date":"2021-10-08T13:11:23","date_gmt":"2021-10-08T13:11:23","guid":{"rendered":"https:\/\/www.vietlearn.org\/post\/?p=1081"},"modified":"2021-10-14T22:10:32","modified_gmt":"2021-10-14T15:10:32","slug":"phuong-trinh-bac-2-mot-an-va-cach-giai-dung-ban-can-biet","status":"publish","type":"post","link":"https:\/\/www.vietlearn.org\/kien-thuc\/phuong-trinh-bac-2-mot-an-va-cach-giai-dung-ban-can-biet\/","title":{"rendered":"Ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 m\u1ed9t \u1ea9n v\u00e0 c\u00e1ch gi\u1ea3i \u0111\u00fang b\u1ea1n c\u1ea7n bi\u1ebft"},"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 to\u00e1n h\u1ecdc, ph\u01b0\u01a1ng tr\u00ecnh v\u00e0 h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh l\u00e0 nh\u1eefng ph\u1ea7n quan tr\u1ecdng c\u00f3 trong ch\u01b0\u01a1ng tr\u00ecnh h\u1ecdc, gi\u00fap <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">h\u1ecdc sinh<\/a> gi\u1ea3i \u0111\u01b0\u1ee3c nhi\u1ec1u b\u00e0i to\u00e1n kh\u00f3 v\u00e0 li\u00ean h\u1ec7 t\u1ed1t v\u1edbi th\u1ef1c ti\u1ec5n. Qua b\u00e0i vi\u1ebft sau \u0111\u00e2y, h\u00e3y c\u00f9ng Vietlearn t\u00ecm hi\u1ec3u v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 m\u1ed9t \u1ea9n c\u00f9ng v\u1edbi c\u00e1ch gi\u1ea3i \u0111\u00fang c\u1ee7a lo\u1ea1i ph\u01b0\u01a1ng tr\u00ecnh n\u00e0y nh\u00e9.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Th\u1ebf n\u00e0o l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh m\u1ed9t \u1ea9n?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u0110\u1ec3 hi\u1ec3u r\u00f5 h\u01a1n v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 1 \u1ea9n, h\u00e3y c\u00f9ng t\u00ecm hi\u1ec3u kh\u00e1i ni\u1ec7m v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh 1 \u1ea9n nh\u00e9.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ph\u01b0\u01a1ng tr\u00ecnh l\u00e0 g\u00ec?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ph\u01b0\u01a1ng tr\u00ecnh l\u00e0 m\u1ed9t thu\u1eadt ng\u1eef trong to\u00e1n h\u1ecdc, d\u00f9ng \u0111\u1ec3 ch\u1ec9 2 bi\u1ec3u th\u1ee9c b\u1eb1ng nhau. Khi bi\u1ec3u di\u1ec5n ph\u01b0\u01a1ng tr\u00ecnh, c\u00e1c b\u1ea1n c\u1ea7n vi\u1ebft 2 bi\u1ec3u th\u1ee9c v\u1ebf tr\u00e1i v\u00e0 v\u1ebf ph\u1ea3i c\u00f9ng v\u1edbi m\u1ed9t d\u1ea5u \u201c=\u2019\u2019 \u1edf gi\u1eefa.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ph\u01b0\u01a1ng tr\u00ecnh m\u1ed9t \u1ea9n l\u00e0 g\u00ec?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ph\u01b0\u01a1ng tr\u00ecnh m\u1ed9t \u1ea9n l\u00e0 m\u1ed9t ph\u01b0\u01a1ng tr\u00ecnh ch\u1ec9 ch\u1ee9a m\u1ed9t bi\u1ebfn duy nh\u1ea5t \u1edf 2 v\u1ebf tr\u00e1i v\u00e0 v\u1ebf ph\u1ea3i. D\u1ea1ng ph\u01b0\u01a1ng tr\u00ecnh m\u1ed9t \u1ea9n n\u00e0y \u0111\u01b0\u1ee3c n\u1ed1i v\u1edbi nhau b\u1edfi d\u1ea5u \u201c\u2018=\u201d. Ph\u01b0\u01a1ng tr\u00ecnh m\u1ed9t \u1ea9n c\u00f3 th\u1ec3 c\u00f3 nhi\u1ec1u b\u1eadc kh\u00e1c nhau nh\u01b0 b\u1eadc 1, b\u1eadc 2 v\u00e0 b\u1eadc 3,\u2026<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 m\u1ed9t \u1ea9n<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 1 \u1ea9n c\u00f2n \u0111\u01b0\u1ee3c g\u1ecdi t\u1eaft l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai. Ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 1 \u1ea9n \u0111\u01b0\u1ee3c vi\u1ebft d\u01b0\u1edbi d\u1ea1ng: ax2 + bx + c = 0. Trong d\u1ea1ng t\u1ed5ng qu\u00e1t n\u00e0y, a, b v\u00e0 c l\u00e0 3 s\u1ed1 \u0111\u00e3 \u0111\u01b0\u1ee3c cho tr\u01b0\u1edbc, a \u2260 0 v\u00e0 x l\u00e0 \u1ea9n s\u1ed1 c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">M\u1ed9t s\u1ed1 v\u00ed d\u1ee5 v\u1ec1 c\u00e1c ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai c\u00f3 ch\u1ee9a m\u1ed9t \u1ea9n:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">2&#215;2 + 3x + 7 =0<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">3&#215;2 + 8x + 5 = 0<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">2&#215;2 + 5x + 7 = 0<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u2026<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u0110\u1ec3 gi\u1ea3i d\u1ea1ng ph\u01b0\u01a1ng tr\u00ecnh n\u00e0y, c\u00e1c b\u1ea1n c\u1ea7n t\u00ecm t\u1eadp nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 ch\u1ee9a \u1ea9n \u0111\u00f3. Ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 ch\u1ee9a m\u1ed9t \u1ea9n l\u00e0 ki\u1ebfn th\u1ee9c \u0111\u01b0\u1ee3c \u0111\u01b0a v\u00e0o ch\u01b0\u01a1ng tr\u00ecnh h\u1ecdc to\u00e1n 9. Do \u0111\u00f3 chuy\u00ean \u0111\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai m\u1ed9t \u1ea9n l\u1edbp 9 l\u00e0 nh\u1eefng ki\u1ebfn th\u1ee9c m\u00e0 <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">h\u1ecdc sinh<\/a> c\u1ea7n ph\u1ea3i n\u1eafm v\u1eefng. Nh\u1edd v\u1eady, c\u00e1c b\u1ea1n <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">h\u1ecdc sinh<\/a> m\u1edbi c\u00f3 th\u1ec3 ti\u1ebfp c\u1eadn \u0111\u01b0\u1ee3c nhi\u1ec1u d\u1ea1ng b\u00e0i t\u1eadp ph\u1ee9c t\u1ea1p h\u01a1n.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">M\u1ed9t s\u1ed1 v\u00ed d\u1ee5 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai m\u1ed9t \u1ea9n<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u00f4ng th\u1ee9c nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 m\u1ed9t \u1ea9n<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u0110\u1ec3 gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 1 \u1ea9n t\u1ed1t nh\u1ea5t, b\u1ea1n c\u1ea7n ph\u1ea3i n\u1eafm \u0111\u01b0\u1ee3c ki\u1ebfn th\u1ee9c v\u1ec1 c\u00f4ng th\u1ee9c nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh n\u00e0y.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Cho ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 ch\u1ee9a 1 \u1ea9n c\u00f3 d\u1ea1ng: ax2 + bx + c = 0 (a \u2260 0). Tr\u01b0\u1edbc ti\u00ean, ta x\u00e9t bi\u1ec7t th\u1ee9c \u0394 = b2 \u2013 4ac. Sau \u0111\u00f3 ph\u00e2n t\u00edch 3 tr\u01b0\u1eddng h\u1ee3p sau \u0111\u00e2y:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Tr\u01b0\u1eddng h\u1ee3p 1: \u0394 &lt; 0 \u21d2 ph\u01b0\u01a1ng tr\u00ecnh v\u00f4 nghi\u1ec7m.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Tr\u01b0\u1eddng h\u1ee3p 2: \u0394 = 0 \u21d2 ph\u01b0\u01a1ng tr\u00ecnh ch\u1ee9a nghi\u1ec7m k\u00e9p .<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Tr\u01b0\u1eddng h\u1ee3p 3: \u0394 &gt; 0 \u21d2 ph\u01b0\u01a1ng tr\u00ecnh c\u00f3 ch\u1ee9a 2 nghi\u1ec7m ph\u00e2n bi\u1ec7t ( v\u00e0 nghi\u1ec7m ).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u00f4ng th\u1ee9c nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 1 \u1ea9n<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">M\u1ed9t s\u1ed1 d\u1ea1ng to\u00e1n v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 1 \u1ea9n th\u01b0\u1eddng g\u1eb7p<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ti\u1ebfp theo, h\u00e3y c\u00f9ng ph\u00e2n t\u00edch m\u1ed9t s\u1ed1 d\u1ea1ng to\u00e1n th\u01b0\u1eddng g\u1eb7p li\u00ean quan \u0111\u1ebfn ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 ch\u1ee9a m\u1ed9t \u1ea9n c\u00e1c b\u1ea1n nh\u00e9. Trong ch\u01b0\u01a1ng tr\u00ecnh h\u1ecdc, c\u00e1c b\u1ea1n s\u1ebd th\u01b0\u1eddng xuy\u00ean g\u1eb7p ph\u1ea3i 4 d\u1ea1ng to\u00e1n c\u01a1 b\u1ea3n.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Nh\u1eefng d\u1ea1ng to\u00e1n th\u01b0\u1eddng g\u1eb7p<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">D\u1ea1ng 1: Nh\u1eadn bi\u1ebft ph\u01b0\u01a1ng tr\u00ecnh<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">D\u1ea1ng b\u00e0i t\u1eadp ph\u1ed5 bi\u1ebfn nh\u1ea5t m\u00e0 b\u1ea1n th\u01b0\u1eddng \u0111\u01b0\u1ee3c g\u1eb7p l\u00e0 nh\u1eadn bi\u1ebft ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai m\u1ed9t \u1ea9n. Khi g\u1eb7p b\u00e0i t\u1eadp n\u00e0y, b\u1ea1n ch\u1ec9 c\u1ea7n ph\u1ea3i n\u1eafm ch\u1eafc \u0111\u1ecbnh ngh\u0129a l\u00e0 \u0111\u00e3 c\u00f3 th\u1ec3 gi\u1ea3i \u0111\u00e1p nhanh ch\u00f3ng.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 c\u00f3 ch\u1ee9a m\u1ed9t \u1ea9n s\u1ebd c\u00f3 d\u1ea1ng: ax2 + bx + c =0. Trong \u0111\u00f3: x l\u00e0 \u1ea9n s\u1ed1, a, b,c l\u00e0 c\u00e1c s\u1ed1 th\u1ef1c v\u1edbi \u0111i\u1ec1u ki\u1ec7n l\u00e0 a \u2260 0.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">D\u1ea1ng 2: Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh c\u00f3 s\u1eed d\u1ee5ng c\u00f4ng th\u1ee9c nghi\u1ec7m<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">D\u1ea1ng b\u00e0i t\u1eadp th\u1ee9 2 c\u00e1c b\u1ea1n <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">h\u1ecdc sinh<\/a> s\u1ebd th\u01b0\u1eddng \u0111\u01b0\u1ee3c g\u1eb7p ph\u1ea3i l\u00e0 gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 c\u00f3 ch\u1ee9a m\u1ed9t \u1ea9n v\u00e0 \u0111\u01b0\u1ee3c ph\u00e9p s\u1eed d\u1ee5ng c\u00f4ng th\u1ee9c nghi\u1ec7m..<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ph\u01b0\u01a1ng ph\u00e1p gi\u1ea3i c\u1ee7a d\u1ea1ng to\u00e1n n\u00e0y l\u00e0 x\u00e9t ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai ax2 + bx + c = 0, t\u00ednh \u0394 = b2 \u2013 4ac sau \u0111\u00f3 x\u00e9t 3 tr\u01b0\u1eddng h\u1ee3p c\u1ee7a \u0394.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">N\u1ebfu \u0394 &lt; 0 th\u00ec ph\u01b0\u01a1ng tr\u00ecnh \u0111\u00e3 cho trong \u0111\u1ec1 b\u00e0i l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh v\u00f4 nghi\u1ec7m.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">N\u1ebfu \u0394 = 0 th\u00ec ph\u01b0\u01a1ng tr\u00ecnh \u0111\u00e3 cho l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh c\u00f3 ch\u1ee9a nghi\u1ec7m k\u00e9p v\u1edbi<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">N\u1ebfu \u0394 &gt; 0 th\u00ec ph\u01b0\u01a1ng tr\u00ecnh \u0111\u00e3 cho l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh c\u00f3 ch\u1ee9a 2 nghi\u1ec7m ph\u00e2n bi\u1ec7t v\u1edbi nghi\u1ec7m v\u00e0 nghi\u1ec7m .<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Sau khi t\u00ecm \u0111\u01b0\u1ee3c nghi\u1ec7m \u0111\u00fang c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh th\u00f4ng qua c\u00f4ng th\u1ee9c nghi\u1ec7m, b\u1ea1n ch\u1ec9 c\u1ea7n k\u1ebft lu\u1eadn nghi\u1ec7m l\u00e0 \u0111\u00e3 ho\u00e0n th\u00e0nh \u0111\u00e1p \u00e1n cho b\u00e0i to\u00e1n.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">D\u1ea1ng 3: Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh kh\u00f4ng s\u1eed d\u1ee5ng c\u00f4ng th\u1ee9c nghi\u1ec7m<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">D\u1ea1ng b\u00e0i t\u1eadp th\u1ee9 3 m\u00e0 c\u00e1c b\u1ea1n s\u1ebd th\u01b0\u1eddng \u0111\u01b0\u1ee3c b\u1eaft g\u1eb7p l\u00e0 gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh nh\u01b0ng kh\u00f4ng s\u1eed d\u1ee5ng c\u00f4ng th\u1ee9c nghi\u1ec7m. C\u00f3 2 c\u00e1ch gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 m\u1ed9t \u1ea9n \u0111\u1ed1i v\u1edbi y\u00eau c\u1ea7u n\u00e0y:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u0110\u01b0a ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai m\u1ed9t \u1ea9n v\u1ec1 d\u01b0\u1edbi d\u1ea1ng m\u1ed9t ph\u01b0\u01a1ng tr\u00ecnh t\u00edch.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u0110\u01b0a v\u1ebf tr\u00e1i c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh th\u00e0nh m\u1ed9t b\u00ecnh ph\u01b0\u01a1ng, v\u1ebf c\u00f2n l\u1ea1i c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh c\u0169ng l\u00e0 b\u00ecnh ph\u01b0\u01a1ng ho\u1eb7c l\u00e0 m\u1ed9t s\u1ed1.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">D\u1ea1ng 4: X\u00e1c \u0111\u1ecbnh s\u1ed1 nghi\u1ec7m<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">X\u00e1c \u0111\u1ecbnh s\u1ed1 nghi\u1ec7m c\u0169ng l\u00e0 m\u1ed9t d\u1ea1ng b\u00e0i t\u1eadp th\u01b0\u1eddng g\u1eb7p \u0111\u1ed1i v\u1edbi ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai c\u00f3 ch\u1ee9a m\u1ed9t \u1ea9n. Ph\u01b0\u01a1ng tr\u00ecnh ax2 + bx + c = 0 v\u00e0 c\u00f3 \u0394 = b2 \u2013 4ac.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">V\u1edbi a \u2260 0 v\u00e0 \u0394 &gt; 0 th\u00ec ph\u01b0\u01a1ng tr\u00ecnh c\u00f3 2 nghi\u1ec7m ph\u00e2n bi\u1ec7t.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">V\u1edbi a \u2260 0 v\u00e0 \u0394 = 0 th\u00ec ph\u01b0\u01a1ng tr\u00ecnh c\u00f3 nghi\u1ec7m k\u00e9p.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">V\u1edbi a \u2260 0 v\u00e0 \u0394 &lt; 0 th\u00ec ph\u01b0\u01a1ng tr\u00ecnh v\u00f4 nghi\u1ec7m.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Trong <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">ch\u01b0\u01a1ng tr\u00ecnh to\u00e1n<\/a> h\u1ecdc, ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 m\u1ed9t \u1ea9n l\u00e0 m\u1ed9t ki\u1ebfn th\u1ee9c v\u00f4 c\u00f9ng quan tr\u1ecdng m\u00e0 c\u00e1c b\u1ea1n <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">h\u1ecdc sinh<\/a> c\u1ea7n ph\u1ea3i n\u1eafm v\u1eefng \u0111\u1ec3 bi\u1ebft c\u00e1ch gi\u1ea3i nhi\u1ec1u ph\u01b0\u01a1ng tr\u00ecnh ph\u1ee9c t\u1ea1p h\u01a1n. \u0110\u1ec3 t\u00ecm hi\u1ec3u th\u00eam v\u1ec1 To\u00e1n v\u00e0 nhi\u1ec1u b\u1ed9 m\u00f4n kh\u00e1c, h\u00e3y truy c\u1eadp ngay v\u00e0o trang web Vietlearn.org\/ nh\u00e9.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u00f4ng th\u1ee9c nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc 2 v\u00e0 c\u00e1ch gi\u1ea3i c\u00e1c d\u1ea1ng<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Gi\u1ea3i to\u00e1n b\u1eb1ng c\u00e1ch l\u1eadp h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh b\u1eb1ng ph\u01b0\u01a1ng ph\u00e1p th\u1ebf \u2013 C\u1ea9m nang \u00f4n luy\u1ec7n<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">H<\/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 to\u00e1n h\u1ecdc, ph\u01b0\u01a1ng tr\u00ecnh v\u00e0 h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh l\u00e0 nh\u1eefng ph\u1ea7n quan tr\u1ecdng c\u00f3 trong ch\u01b0\u01a1ng tr\u00ecnh h\u1ecdc, gi\u00fap h\u1ecdc sinh gi\u1ea3i \u0111\u01b0\u1ee3c nhi\u1ec1u b\u00e0i to\u00e1n kh\u00f3 v\u00e0 li\u00ean h\u1ec7 t\u1ed1t v\u1edbi th\u1ef1c ti\u1ec5n. Qua b\u00e0i vi\u1ebft sau \u0111\u00e2y, h\u00e3y c\u00f9ng Vietlearn t\u00ecm hi\u1ec3u v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc [&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":[9],"tags":[],"class_list":["post-1081","post","type-post","status-publish","format-standard","hentry","category-toan-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/1081","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=1081"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/1081\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=1081"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=1081"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=1081"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}