{"id":1069,"date":"2021-10-08T13:09:44","date_gmt":"2021-10-08T13:09:44","guid":{"rendered":"https:\/\/www.vietlearn.org\/post\/?p=1069"},"modified":"2021-10-14T22:11:32","modified_gmt":"2021-10-14T15:11:32","slug":"phuong-trinh-quy-ve-phuong-trinh-bac-nhat-bac-hai-hoc-toan-9","status":"publish","type":"post","link":"https:\/\/www.vietlearn.org\/kien-thuc\/phuong-trinh-quy-ve-phuong-trinh-bac-nhat-bac-hai-hoc-toan-9\/","title":{"rendered":"Ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t b\u1eadc hai \u2013 H\u1ecdc To\u00e1n 9"},"content":{"rendered":"\n<p>Ghi ch\u00fa: T\u00e0i li\u1ec7u tr\u00edch d\u1eabn<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t b\u1eadc hai l\u00e0 ph\u1ea7n ki\u1ebfn th\u1ee9c c\u00e1c em s\u1ebd \u0111\u01b0\u1ee3c h\u1ecdc \u1edf l\u1edbp 9. \u0110\u00e2y l\u00e0 n\u1ed9i dung kh\u00e1 quan tr\u1ecdng \u0111\u1ec3 c\u00f3 th\u1ec3 l\u00e0m c\u00e1c b\u00e0i t\u1eadp ti\u1ebfp theo. V\u1eady n\u00ean, vi\u1ec7c h\u1ec7 th\u1ed1ng l\u1ea1i l\u00e0 \u0111i\u1ec1u c\u1ef1c k\u1ef3 c\u1ea7n thi\u1ebft. C\u00f9ng Vietlearn \u00f4n l\u1ea1i c\u00e1c l\u00fd thuy\u1ebft b\u00e0i 7 ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai v\u00e0 t\u00ecm hi\u1ec3u v\u1ec1 m\u1ed9t s\u1ed1 d\u1ea1ng b\u00e0i t\u1eadp c\u00f3 li\u00ean quan trong b\u00e0i vi\u1ebft sau.<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t b\u1eadc hai<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t<\/p>\n\n\n\n<p>C\u00e1ch gi\u1ea3i v\u00e0 bi\u1ec7n lu\u1eadn ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t d\u1ea1ng ax + b = 0 (1) \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n nh\u01b0 sau:<\/p>\n\n\n\n<p>a \u2260 0: (1) c\u00f3 nghi\u1ec7m duy nh\u1ea5t<\/p>\n\n\n\n<p>a = 0; b \u2260 0 (1) v\u00f4 nghi\u1ec7m.<\/p>\n\n\n\n<p>a = 0; b = 0: (1) nghi\u1ec7m \u0111\u00fang v\u1edbi m\u1ecdi x\u2208R.<\/p>\n\n\n\n<p>Khi a \u2260 0 ph\u01b0\u01a1ng tr\u00ecnh ax + b = 0 \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n.<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai m\u1ed9t \u1ea9n ax2 + bx + c = 0 (a \u2260 0) (2)<\/p>\n\n\n\n<p>\u0394 = b2 \u2212 4ac \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 bi\u1ec7t th\u1ee9c c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh (2).<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u0394 &gt; 0 th\u00ec (2) c\u00f3 2 nghi\u1ec7m ph\u00e2n bi\u1ec7t<\/li><li>\u0394 = 0 th\u00ec (2) c\u00f3 nghi\u1ec7m k\u00e9p<\/li><li>\u0394 &lt; 0 th\u00ec (2) v\u00f4 nghi\u1ec7m.<\/li><\/ul>\n\n\n\n<p>\u0110\u1ecbnh l\u00ed Vi\u2013\u00e9t<\/p>\n\n\n\n<p>N\u1ebfu ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai ax2 + bx + c = 0 (a \u2260 0) c\u00f3 hai nghi\u1ec7m x1, x2 th\u00ec<\/p>\n\n\n\n<p>Ng\u01b0\u1ee3c l\u1ea1i, n\u1ebfu hai s\u1ed1 u v\u00e0 v c\u00f3 t\u1ed5ng u + v = S v\u00e0 t\u00edch u.v = P th\u00ec u v\u00e0 v l\u00e0 c\u00e1c nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh x2 \u2013 Sx + P = 0.<\/p>\n\n\n\n<p>C\u00e1c d\u1ea1ng b\u00e0i t\u1eadp ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai l\u1edbp 9<\/p>\n\n\n\n<p>C\u00e1c d\u1ea1ng b\u00e0i t\u1eadp v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t b\u1eadc hai th\u01b0\u1eddng g\u1eb7p nh\u01b0 sau:<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh tr\u00f9ng ph\u01b0\u01a1ng<\/p>\n\n\n\n<p>\u0110\u1ecbnh ngh\u0129a: Ph\u01b0\u01a1ng tr\u00ecnh tr\u00f9ng ph\u01b0\u01a1ng l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh c\u00f3 d\u1ea1ng:<\/p>\n\n\n\n<p>ax4 + bx2 + c = 0 (a \u2260 0)<\/p>\n\n\n\n<p>C\u00e1ch gi\u1ea3i:<\/p>\n\n\n\n<p>Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh tr\u00f9ng ph\u01b0\u01a1ng ax4 + bx2 + c = 0 (a \u2260 0)<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u0110\u1eb7t x2 = t, t \u2265 0<\/li><li>Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh at2 + bt + c = 0<\/li><li>V\u1edbi m\u1ed7i gi\u00e1 tr\u1ecb t\u00ecm \u0111\u01b0\u1ee3c c\u1ee7a t (th\u1ecfa m\u00e3n t \u2265 0), l\u1ea1i gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh x2 = t.<\/li><\/ul>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh ch\u1ee9a \u1ea9n \u1edf m\u1eabu th\u1ee9c<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 b\u1eadc nh\u1ea5t b\u1eadc hai ch\u1ee9a \u1ea9n \u1edf m\u1eabu th\u1ee9c khi gi\u1ea3i ta l\u00e0m nh\u01b0 sau:<\/p>\n\n\n\n<p>B\u01b0\u1edbc 1: T\u00ecm \u0111i\u1ec1u ki\u1ec7n x\u00e1c \u0111\u1ecbnh c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh.<\/p>\n\n\n\n<p>B\u01b0\u1edbc 2: Quy \u0111\u1ed3ng m\u1eabu th\u1ee9c hai v\u1ebf r\u1ed3i kh\u1eed m\u1eabu th\u1ee9c.<\/p>\n\n\n\n<p>B\u01b0\u1edbc 3: Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh v\u1eeba nh\u1eadn \u0111\u01b0\u1ee3c.<\/p>\n\n\n\n<p>B\u01b0\u1edbc 4: Trong c\u00e1c gi\u00e1 tr\u1ecb t\u00ecm \u0111\u01b0\u1ee3c c\u1ee7a \u1ea9n, lo\u1ea1i c\u00e1c gi\u00e1 tr\u1ecb kh\u00f4ng th\u1ecfa m\u00e3n \u0111i\u1ec1u ki\u1ec7n x\u00e1c \u0111\u1ecbnh, c\u00e1c gi\u00e1 tr\u1ecb th\u1ecfa m\u00e3n \u0111i\u1ec1u ki\u1ec7n x\u00e1c \u0111\u1ecbnh l\u00e0 nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh \u0111\u00e3 cho.<\/p>\n\n\n\n<p>C\u00f3 nhi\u1ec1u d\u1ea1ng b\u00e0i v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh ch\u1ee9a \u1ea9n trong d\u1ea5u gi\u00e1 tr\u1ecb tuy\u1ec7t \u0111\u1ed1i<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai l\u1edbp 9 ch\u1ee9a \u1ea9n trong d\u1ea5u gi\u00e1 tr\u1ecb tuy\u1ec7t \u0111\u1ed1i c\u00e1ch gi\u1ea3i l\u00e0 d\u00f9ng \u0111\u1ecbnh ngh\u0129a c\u1ee7a gi\u00e1 tr\u1ecb tuy\u1ec7t \u0111\u1ed1i ho\u1eb7c b\u00ecnh ph\u01b0\u01a1ng hai v\u1ebf \u0111\u1ec3 kh\u1eed d\u1ea5u gi\u00e1 tr\u1ecb tuy\u1ec7t \u0111\u1ed1i.<\/p>\n\n\n\n<p>V\u00ed d\u1ee5 1. Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh |x \u2013 3| = 2x + 1. (3)<\/p>\n\n\n\n<p>C\u00e1ch gi\u1ea3i:<\/p>\n\n\n\n<p>C\u00e1ch 1<\/p>\n\n\n\n<p>a) N\u1ebfu x \u2265 3 th\u00ec ph\u01b0\u01a1ng tr\u00ecnh (3) tr\u1edf th\u00e0nh x \u2013 3 = 2x + 1. T\u1eeb \u0111\u00f3 x = \u20134.<\/p>\n\n\n\n<p>Gi\u00e1 tr\u1ecb x = \u20134 kh\u00f4ng th\u1ecfa m\u00e3n \u0111i\u1ec1u ki\u1ec7n x \u2265 3 n\u00ean b\u1ecb lo\u1ea1i.<\/p>\n\n\n\n<p>b) N\u1ebfu x &lt; 3 th\u00ec ph\u01b0\u01a1ng tr\u00ecnh (3) tr\u1edf th\u00e0nh \u2013x + 3 = 2x + 1. T\u1eeb \u0111\u00f3<\/p>\n\n\n\n<p>Gi\u00e1 tr\u1ecb n\u00e0y th\u1ecfa m\u00e3n \u0111i\u1ec1u ki\u1ec7n x &lt; 3 n\u00ean l\u00e0 nghi\u1ec7m.<\/p>\n\n\n\n<p>K\u1ebft lu\u1eadn. V\u1eady nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh l\u00e0 x = 23<\/p>\n\n\n\n<p>C\u00e1ch 2.<\/p>\n\n\n\n<p>B\u00ecnh ph\u01b0\u01a1ng hai v\u1ebf c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh (3) ta \u0111\u01b0a t\u1edbi ph\u01b0\u01a1ng tr\u00ecnh h\u1ec7 qu\u1ea3<\/p>\n\n\n\n<p>(3) =&gt; (x \u2013 3)2 = (2x + 1)2<\/p>\n\n\n\n<p>=&gt; x2 \u2013 6x + 9 = 4&#215;2 + 4x + 1<\/p>\n\n\n\n<p>=&gt; 3&#215;2 + 10x \u2013 8 = 0.<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh cu\u1ed1i c\u00f3 hai nghi\u1ec7m l\u00e0 x = \u20134 v\u00e0<\/p>\n\n\n\n<p>Th\u1eed l\u1ea1i ta th\u1ea5y ph\u01b0\u01a1ng tr\u00ecnh (3) ch\u1ec9 c\u00f3 nghi\u1ec7m l\u00e0<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh ch\u1ee9a \u1ea9n d\u01b0\u1edbi d\u1ea5u c\u0103n<\/p>\n\n\n\n<p>\u0110\u1ec3 gi\u1ea3i c\u00e1c ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t b\u1eadc hai c\u00f3 ch\u1ee9a \u1ea9n d\u01b0\u1edbi d\u1ea5u c\u0103n b\u1eadc hai, ta th\u01b0\u1eddng b\u00ecnh ph\u01b0\u01a1ng hai v\u1ebf \u0111\u1ec3 \u0111\u01b0a v\u1ec1 m\u1ed9t ph\u01b0\u01a1ng tr\u00ecnh h\u1ec7 qu\u1ea3 kh\u00f4ng ch\u1ee9a \u1ea9n d\u01b0\u1edbi d\u1ea5u c\u0103n.<\/p>\n\n\n\n<p>V\u00ed d\u1ee5 2. Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh = x \u2013 2 (4).<\/p>\n\n\n\n<p>C\u00e1ch gi\u1ea3i<\/p>\n\n\n\n<p>\u0110i\u1ec1u ki\u1ec7n c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh (4) l\u00e0<\/p>\n\n\n\n<p>B\u00ecnh ph\u01b0\u01a1ng hai v\u1ebf c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh (4) ta \u0111\u01b0a t\u1edbi ph\u01b0\u01a1ng tr\u00ecnh h\u1ec7 qu\u1ea3<\/p>\n\n\n\n<p>(4) =&gt; 2x \u2013 3 = x2 \u2013 4x + 4<\/p>\n\n\n\n<p>=&gt; x2 \u2013 6x + 7 = 0.<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh cu\u1ed1i c\u00f3 hai nghi\u1ec7m l\u00e0 x = 3 + \u221a2 v\u00e0 x = 3 \u2013 \u221a2 . C\u1ea3 hai gi\u00e1 tr\u1ecb n\u00e0y \u0111\u1ec1u th\u1ecfa m\u00e3n \u0111i\u1ec1u ki\u1ec7n c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh (4), nh\u01b0ng khi thay v\u00e0o ph\u01b0\u01a1ng tr\u00ecnh (4) th\u00ec gi\u00e1 tr\u1ecb x = 3 \u2013 \u221a2 b\u1ecb lo\u1ea1i (v\u1ebf tr\u00e1i d\u01b0\u01a1ng c\u00f2n v\u1ebf ph\u1ea3i \u00e2m), c\u00f2n gi\u00e1 tr\u1ecb x= 3 + \u221a2 l\u00e0 nghi\u1ec7m (hai v\u1ebf c\u00f9ng b\u1eb1ng \u221a2 + 1).<\/p>\n\n\n\n<p>K\u1ebft lu\u1eadn. V\u1eady nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh (4) l\u00e0 x= 3 + \u221a2.<\/p>\n\n\n\n<p>Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai ch\u1ee9a \u1ea9n \u1edf m\u1eabu th\u1ee9c<\/p>\n\n\n\n<p>\u0110\u1ec3 gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai ch\u1ee9a \u1ea9n \u1edf m\u1eabu th\u1ee9c, ta c\u00f3 c\u00e1c b\u01b0\u1edbc gi\u1ea3i nh\u01b0 sau:<\/p>\n\n\n\n<p>B\u01b0\u1edbc 1. T\u00ecm \u0111i\u1ec1u ki\u1ec7n x\u00e1c \u0111\u1ecbnh c\u1ee7a \u1ea9n c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh.<\/p>\n\n\n\n<p>B\u01b0\u1edbc 2. Quy \u0111\u1ed3ng m\u1eabu th\u1ee9c hai v\u1ebf r\u1ed3i kh\u1eed m\u1eabu.<\/p>\n\n\n\n<p>B\u01b0\u1edbc 3. Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh v\u1eeba nh\u1eadn \u0111\u01b0\u1ee3c \u1edf b\u01b0\u1edbc 2.<\/p>\n\n\n\n<p>B\u01b0\u1edbc 4. So s\u00e1nh c\u00e1c nghi\u1ec7m t\u00ecm \u0111\u01b0\u1ee3c \u1edf b\u01b0\u1edbc 3 v\u1edbi \u0111i\u1ec1u ki\u1ec7n x\u00e1c \u0111\u1ecbnh v\u00e0 k\u1ebft lu\u1eadn.<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng tr\u00ecnh \u0111\u01b0a v\u1ec1 d\u1ea1ng ph\u01b0\u01a1ng tr\u00ecnh t\u00edch<\/p>\n\n\n\n<p>B\u01b0\u1edbc 1. Ph\u00e2n t\u00edch v\u1ebf tr\u00e1i th\u00e0nh nh\u00e2n t\u1eed, v\u1ebf ph\u1ea3i b\u1eb1ng 0.<\/p>\n\n\n\n<p>B\u01b0\u1edbc 2. X\u00e9t t\u1eebng nh\u00e2n t\u1eed b\u1eb1ng 0 \u0111\u1ec3 t\u00ecm nghi\u1ec7m.<\/p>\n\n\n\n<p>Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh b\u1eb1ng c\u00e1ch \u0111\u1eb7t \u1ea9n ph\u1ee5<\/p>\n\n\n\n<p>B\u01b0\u1edbc 1. T\u00ecm \u0111i\u1ec1u ki\u1ec7n x\u00e1c \u0111\u1ecbnh (n\u1ebfu c\u00f3)<\/p>\n\n\n\n<p>B\u01b0\u1edbc 2. \u0110\u1eb7t \u1ea9n ph\u1ee5 v\u00e0 gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh theo \u1ea9n m\u1edbi<\/p>\n\n\n\n<p>B\u01b0\u1edbc 3. T\u00ecm nghi\u1ec7m ban \u0111\u1ea7u v\u00e0 so s\u00e1nh v\u1edbi \u0111i\u1ec1u ki\u1ec7n x\u00e1c \u0111\u1ecbnh \u1edf b\u01b0\u1edbc 1 \u0111\u1ec3 k\u1ebft lu\u1eadn nghi\u1ec7m.<\/p>\n\n\n\n<p>Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh ch\u1ee9a c\u0103n th\u1ee9c<\/p>\n\n\n\n<p>B\u01b0\u1edbc 1: \u0110i\u1ec1u ki\u1ec7n x\u00e1c \u0111\u1ecbnh<\/p>\n\n\n\n<p>B\u01b0\u1edbc 2: L\u00e0m m\u1ea5t d\u1ea5u c\u0103n b\u1eb1ng c\u00e1ch \u0111\u1eb7t \u1ea9n ph\u1ee5 ho\u1eb7c l\u0169y th\u1eeba hai v\u1ebf sau \u0111\u00f3 gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh.<\/p>\n\n\n\n<p>B\u01b0\u1edbc 3: So s\u00e1nh \u0111i\u1ec1u ki\u1ec7n v\u00e0 k\u1ebft lu\u1eadn nghi\u1ec7m.<\/p>\n\n\n\n<p>M\u1ed9t s\u1ed1 d\u1ea1ng kh\u00e1c<\/p>\n\n\n\n<p>Ta c\u00f3 th\u1ec3 d\u00f9ng h\u1eb1ng \u0111\u1eb3ng th\u1ee9c, th\u00eam b\u1edbt h\u1ea1ng t\u1eed, ho\u1eb7c \u0111\u00e1nh gi\u00e1 hai v\u1ebf\u2026 \u0111\u1ec3 gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh.<\/p>\n\n\n\n<p>T\u00ecm hi\u1ec3u th\u00eam c\u00e1c ki\u1ebfn th\u1ee9c m\u00f4n To\u00e1n t\u1ea1i Vietlearn.vn<\/p>\n\n\n\n<p>C\u00e1c d\u1ea1ng b\u00e0i t\u1eadp ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai r\u1ea5t \u0111a d\u1ea1ng. \u0110\u1ec3 c\u00e1c em c\u00f3 th\u1ec3 l\u00e0m quen v\u1edbi c\u00e1c d\u1ea1ng b\u00e0i t\u1eadp n\u00e0y t\u1ed1t h\u01a1n, h\u00e3y t\u00ecm hi\u1ec3u th\u00eam t\u1ea1i \u0111\u1ecba ch\u1ec9 Vietlearn.org\/.<\/p>\n\n\n\n<p><\/p>\n\n\n\n<p>H\u1ec7 th\u1ee9c vi-\u00e9t v\u00e0 \u1ee9ng d\u1ee5ng<\/p>\n\n\n\n<p>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>H\u1ec7 hai ph\u01b0\u01a1ng tr\u00ecnh b\u1ead<\/p>\n\n\n\n\n\n\n","protected":false},"excerpt":{"rendered":"<p>Ghi ch\u00fa: T\u00e0i li\u1ec7u tr\u00edch d\u1eabn Ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t b\u1eadc hai l\u00e0 ph\u1ea7n ki\u1ebfn th\u1ee9c c\u00e1c em s\u1ebd \u0111\u01b0\u1ee3c h\u1ecdc \u1edf l\u1edbp 9. \u0110\u00e2y l\u00e0 n\u1ed9i dung kh\u00e1 quan tr\u1ecdng \u0111\u1ec3 c\u00f3 th\u1ec3 l\u00e0m c\u00e1c b\u00e0i t\u1eadp ti\u1ebfp theo. V\u1eady n\u00ean, vi\u1ec7c h\u1ec7 th\u1ed1ng l\u1ea1i l\u00e0 \u0111i\u1ec1u c\u1ef1c k\u1ef3 c\u1ea7n [&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":[9,4],"tags":[],"class_list":["post-1069","post","type-post","status-publish","format-standard","hentry","category-toan-hoc","category-trung-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/1069","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=1069"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/1069\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=1069"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=1069"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=1069"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}