{"id":2812,"date":"2026-10-15T11:34:45","date_gmt":"2026-10-15T04:34:45","guid":{"rendered":"https:\/\/navi.edu.vn\/blog\/?p=2812"},"modified":"2026-10-15T11:39:06","modified_gmt":"2026-10-15T04:39:06","slug":"de-cuong-on-tap-giua-ky-1-toan-9-2026-2027","status":"publish","type":"post","link":"https:\/\/navi.edu.vn\/blog\/de-cuong-on-tap-giua-ky-1-toan-9-2026-2027\/","title":{"rendered":"\u0110\u1ec1 c\u01b0\u01a1ng \u00f4n t\u1eadp gi\u1eefa k\u1ef3 1 To\u00e1n 9 (2026-2027) &#038; \u0110\u1ec1 thi m\u1eabu c\u00f3 \u0111\u00e1p \u00e1n"},"content":{"rendered":"<p data-path-to-node=\"0\">K\u1ef3 thi gi\u1eefa h\u1ecdc k\u1ef3 1 l\u1edbp 9 ch\u00ednh l\u00e0 b\u00e0i ki\u1ec3m tra b\u01b0\u1edbc ngo\u1eb7t quan tr\u1ecdng \u0111\u1ea7u ti\u00ean c\u1ee7a n\u0103m h\u1ecdc cu\u1ed1i c\u1ea5p. K\u1ebft qu\u1ea3 b\u00e0i thi kh\u00f4ng ch\u1ec9 \u1ea3nh h\u01b0\u1edfng tr\u1ef1c ti\u1ebfp \u0111\u1ebfn \u0111i\u1ec3m s\u1ed1 h\u1ecdc b\u1ea1 m\u00e0 c\u00f2n ph\u1ea3n \u00e1nh ch\u00ednh x\u00e1c th\u1ef1c l\u1ef1c hi\u1ec7n t\u1ea1i c\u1ee7a h\u1ecdc sinh, gi\u00fap gia \u0111\u00ecnh k\u1ecbp th\u1eddi \u0111\u1ecbnh h\u00ecnh l\u1ea1i <span style=\"text-decoration: underline;\"><strong>l\u1ed9 tr\u00ecnh luy\u1ec7n thi v\u00e0o 10<\/strong><\/span> ngay t\u1eeb \u0111\u1ea7u n\u0103m. Nh\u1eb1m gi\u00fap c\u00e1c em gi\u1ea3i t\u1ecfa \u00e1p l\u1ef1c v\u00e0 \u00f4n thi \u0111\u00fang h\u01b0\u1edbng, NaviEdu t\u1ed5ng h\u1ee3p tr\u1ecdn b\u1ed9 <b data-path-to-node=\"2\" data-index-in-node=\"80\">\u0111\u1ec1 c\u01b0\u01a1ng \u00f4n t\u1eadp gi\u1eefa k\u1ef3 1 to\u00e1n 9<\/b> c\u00f4 \u0111\u1ecdng nh\u1ea5t. C\u1ea9m nang s\u1ebd h\u1ec7 th\u1ed1ng h\u00f3a to\u00e0n b\u1ed9 l\u00fd thuy\u1ebft c\u1ed1t l\u00f5i, ch\u1ecdn l\u1ecdc c\u00e1c d\u1ea1ng b\u00e0i k\u00e8m ph\u01b0\u01a1ng ph\u00e1p gi\u1ea3i chi ti\u1ebft, ma tr\u1eadn \u0111\u1ec1 thi m\u1eabu v\u00e0 link t\u1ea3i t\u00e0i li\u1ec7u PDF \u0111\u1ed9c quy\u1ec1n gi\u00fap h\u1ecdc sinh t\u1ef1 tin b\u1ee9t ph\u00e1 \u0111i\u1ec3m 8+!<\/p>\n<h2 style=\"color: #0056b3; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; margin-top: 35px; font-size: 20px;\">C\u1ea5u tr\u00fac ma tr\u1eadn \u0111\u1ec1 thi gi\u1eefa k\u1ef3 1 To\u00e1n 9 (Ch\u01b0\u01a1ng tr\u00ecnh GDPT m\u1edbi)<\/h2>\n<figure id=\"attachment_2824\" aria-describedby=\"caption-attachment-2824\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-2824 size-full\" src=\"https:\/\/navi.edu.vn\/blog\/wp-content\/uploads\/2026\/10\/de-cuong-on-tap-giua-ky-1-toan-9-2026-2027-1.png\" alt=\"T\u00ecm hi\u1ec3u v\u1ec1 c\u1ea5u tr\u00fac ma tr\u1eadn \u0111\u1ec1 thi gi\u1eefa h\u1ecdc k\u1ef3 1 To\u00e1n 9\" width=\"800\" height=\"500\" srcset=\"https:\/\/navi.edu.vn\/blog\/wp-content\/uploads\/2026\/10\/de-cuong-on-tap-giua-ky-1-toan-9-2026-2027-1.png 800w, https:\/\/navi.edu.vn\/blog\/wp-content\/uploads\/2026\/10\/de-cuong-on-tap-giua-ky-1-toan-9-2026-2027-1-300x188.png 300w, https:\/\/navi.edu.vn\/blog\/wp-content\/uploads\/2026\/10\/de-cuong-on-tap-giua-ky-1-toan-9-2026-2027-1-768x480.png 768w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-2824\" class=\"wp-caption-text\">T\u00ecm hi\u1ec3u v\u1ec1 c\u1ea5u tr\u00fac ma tr\u1eadn \u0111\u1ec1 thi gi\u1eefa h\u1ecdc k\u1ef3 1 To\u00e1n 9<\/figcaption><\/figure>\n<p data-path-to-node=\"1\">Hi\u1ec3u r\u00f5 c\u1ea5u tr\u00fac v\u00e0 ma tr\u1eadn \u0111\u1ec1 thi l\u00e0 b\u01b0\u1edbc quan tr\u1ecdng gi\u00fap h\u1ecdc sinh ph\u00e2n b\u1ed5 th\u1eddi gian \u00f4n t\u1eadp h\u1ee3p l\u00fd, tr\u00e1nh t\u00ecnh tr\u1ea1ng &#8220;h\u1ecdc t\u1ee7&#8221; ho\u1eb7c sa \u0111\u00e0 v\u00e0o nh\u1eefng c\u00e2u qu\u00e1 kh\u00f3 m\u00e0 b\u1ecf l\u1ee1 \u0111i\u1ec3m s\u1ed1 \u1edf c\u00e1c ph\u1ea7n c\u01a1 b\u1ea3n. \u0110\u1ec1 thi gi\u1eefa k\u1ef3 1 To\u00e1n 9 theo \u0111\u1ecbnh h\u01b0\u1edbng ch\u01b0\u01a1ng tr\u00ecnh m\u1edbi \u0111\u01b0\u1ee3c chu\u1ea9n h\u00f3a ch\u1eb7t ch\u1ebd v\u1ec1 t\u1ef7 l\u1ec7 \u0111i\u1ec3m s\u1ed1 v\u00e0 ph\u00e2n t\u1ea7ng theo 4 c\u1ea5p \u0111\u1ed9 t\u01b0 duy:<\/p>\n<ul data-path-to-node=\"2\">\n<li>\n<p data-path-to-node=\"2,0,0\"><b data-path-to-node=\"2,0,0\" data-index-in-node=\"0\">T\u1ef7 l\u1ec7 ph\u00e2n b\u1ed5 n\u1ed9i dung:<\/b> Ph\u1ea7n \u0110\u1ea1i s\u1ed1 chi\u1ebfm kho\u1ea3ng <b data-path-to-node=\"2,0,0\" data-index-in-node=\"49\">65% &#8211; 70%<\/b> t\u1ed5ng \u0111i\u1ec3m (t\u1eadp trung v\u00e0o ph\u01b0\u01a1ng tr\u00ecnh, h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh, b\u1ea5t \u0111\u1eb3ng th\u1ee9c v\u00e0 h\u00e0m s\u1ed1 b\u1eadc nh\u1ea5t). Ph\u1ea7n H\u00ecnh h\u1ecdc chi\u1ebfm <b data-path-to-node=\"2,0,0\" data-index-in-node=\"170\">30% &#8211; 35%<\/b> t\u1ed5ng \u0111i\u1ec3m (tr\u1ecdng t\u00e2m l\u00e0 h\u1ec7 th\u1ee9c l\u01b0\u1ee3ng v\u00e0 t\u1ec9 s\u1ed1 l\u01b0\u1ee3ng gi\u00e1c trong tam gi\u00e1c vu\u00f4ng).<\/p>\n<\/li>\n<li>\n<p data-path-to-node=\"2,1,0\"><b data-path-to-node=\"2,1,0\" data-index-in-node=\"0\">T\u1ef7 l\u1ec7 c\u1ea5p \u0111\u1ed9 nh\u1eadn th\u1ee9c:<\/b> \u0110\u1ec1 thi \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf c\u00e2n b\u1eb1ng v\u1edbi 60% \u0111i\u1ec3m s\u1ed1 d\u00e0nh cho nh\u00f3m nh\u1eadn bi\u1ebft &#8211; th\u00f4ng hi\u1ec3u (m\u1ee5c ti\u00eau 5 &#8211; 6 \u0111i\u1ec3m) v\u00e0 40% \u0111i\u1ec3m s\u1ed1 cho nh\u00f3m v\u1eadn d\u1ee5ng &#8211; v\u1eadn d\u1ee5ng cao (ph\u00e2n h\u00f3a h\u1ecdc sinh kh\u00e1, gi\u1ecfi \u0111\u1ea1t m\u1ed1c 8 &#8211; 10 \u0111i\u1ec3m).<\/p>\n<\/li>\n<\/ul>\n<p data-path-to-node=\"3\">D\u01b0\u1edbi \u0111\u00e2y l\u00e0 b\u1ea3ng ma tr\u1eadn \u0111\u1ec1 thi tham kh\u1ea3o chi ti\u1ebft:<\/p>\n<div id=\"model-response-message-contentr_16ab4d19c80e825f\" class=\"markdown markdown-main-panel md-content enable-luminous-fast-follows enable-updated-hr-color tutor-markdown-rendering\" dir=\"ltr\" aria-busy=\"false\" aria-live=\"off\">\n<table data-path-to-node=\"4\">\n<thead>\n<tr>\n<td><strong>Ch\u1ee7 \u0111\u1ec1 ki\u1ebfn th\u1ee9c<\/strong><\/td>\n<td><strong>Nh\u1eadn bi\u1ebft (30%)<\/strong><\/td>\n<td><strong>Th\u00f4ng hi\u1ec3u (30%)<\/strong><\/td>\n<td><strong>V\u1eadn d\u1ee5ng (30%)<\/strong><\/td>\n<td><strong>V\u1eadn d\u1ee5ng cao (10%)<\/strong><\/td>\n<td><strong>T\u1ed5ng \u0111i\u1ec3m \u01b0\u1edbc t\u00ednh<\/strong><\/td>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td><span data-path-to-node=\"4,1,0,0\"><b data-path-to-node=\"4,1,0,0\" data-index-in-node=\"0\">1. Ph\u01b0\u01a1ng tr\u00ecnh &amp; H\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh<\/b><\/span><\/td>\n<td><span data-path-to-node=\"4,1,1,0\">Nh\u1eadn bi\u1ebft d\u1ea1ng ph\u01b0\u01a1ng tr\u00ecnh t\u00edch, ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t 2 \u1ea9n<\/span><\/td>\n<td><span data-path-to-node=\"4,1,2,0\">Gi\u1ea3i h\u1ec7 2 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t 2 \u1ea9n c\u01a1 b\u1ea3n<\/span><\/td>\n<td><span data-path-to-node=\"4,1,3,0\">Gi\u1ea3i b\u00e0i to\u00e1n b\u1eb1ng c\u00e1ch l\u1eadp h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh (chuy\u1ec3n \u0111\u1ed9ng, n\u0103ng su\u1ea5t)<\/span><\/td>\n<td><span data-path-to-node=\"4,1,4,0\">H\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh ch\u1ee9a tham s\u1ed1, h\u1ec7 \u0111\u1ed1i x\u1ee9ng ho\u1eb7c \u0111\u1eb7t \u1ea9n ph\u1ee5 kh\u00f3<\/span><\/td>\n<td><span data-path-to-node=\"4,1,5,0\"><b data-path-to-node=\"4,1,5,0\" data-index-in-node=\"0\">3.0 \u2013 3.5 \u0111i\u1ec3m<\/b><\/span><\/td>\n<\/tr>\n<tr>\n<td><span data-path-to-node=\"4,2,0,0\"><b data-path-to-node=\"4,2,0,0\" data-index-in-node=\"0\">2. B\u1ea5t \u0111\u1eb3ng th\u1ee9c &amp; B\u1ea5t ph\u01b0\u01a1ng tr\u00ecnh<\/b><\/span><\/td>\n<td><span data-path-to-node=\"4,2,1,0\">Nh\u1eadn bi\u1ebft nghi\u1ec7m b\u1ea5t ph\u01b0\u01a1ng tr\u00ecnh, t\u00ednh ch\u1ea5t c\u01a1 b\u1ea3n<\/span><\/td>\n<td><span data-path-to-node=\"4,2,2,0\">Gi\u1ea3i b\u1ea5t ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n v\u00e0 bi\u1ec3u di\u1ec5n tr\u1ee5c s\u1ed1<\/span><\/td>\n<td><span data-path-to-node=\"4,2,3,0\">\u1ee8ng d\u1ee5ng b\u1ea5t ph\u01b0\u01a1ng tr\u00ecnh gi\u1ea3i b\u00e0i to\u00e1n th\u1ef1c t\u1ebf<\/span><\/td>\n<td><span data-path-to-node=\"4,2,4,0\">Ch\u1ee9ng minh b\u1ea5t \u0111\u1eb3ng th\u1ee9c t\u00ecm GTLN, GTNN (d\u1ea1ng ph\u00e2n lo\u1ea1i \u0111i\u1ec3m 10)<\/span><\/td>\n<td><span data-path-to-node=\"4,2,5,0\"><b data-path-to-node=\"4,2,5,0\" data-index-in-node=\"0\">1.5 \u2013 2.0 \u0111i\u1ec3m<\/b><\/span><\/td>\n<\/tr>\n<tr>\n<td><span data-path-to-node=\"4,3,0,0\"><b data-path-to-node=\"4,3,0,0\" data-index-in-node=\"0\">3. H\u00e0m s\u1ed1 b\u1eadc nh\u1ea5t <span class=\"math-inline\" data-math=\"y = ax + b\" data-index-in-node=\"19\">$y = ax + b$<\/span><\/b><\/span><\/td>\n<td><span data-path-to-node=\"4,3,1,0\">Nh\u1eadn di\u1ec7n h\u00e0m s\u1ed1 \u0111\u1ed3ng bi\u1ebfn, ngh\u1ecbch bi\u1ebfn<\/span><\/td>\n<td><span data-path-to-node=\"4,3,2,0\">V\u1ebd \u0111\u1ed3 th\u1ecb, t\u00ecm t\u1ecda \u0111\u1ed9 giao \u0111i\u1ec3m, x\u00e9t v\u1ecb tr\u00ed t\u01b0\u01a1ng \u0111\u1ed1i<\/span><\/td>\n<td><span data-path-to-node=\"4,3,3,0\">X\u00e1c \u0111\u1ecbnh h\u1ec7 s\u1ed1 <span class=\"math-inline\" data-math=\"a, b\" data-index-in-node=\"15\">$a, b$<\/span> th\u1ecfa m\u00e3n \u0111i\u1ec1u ki\u1ec7n h\u00ecnh h\u1ecdc\/kho\u1ea3ng c\u00e1ch<\/span><\/td>\n<td><span data-path-to-node=\"4,3,4,0\">B\u00e0i to\u00e1n t\u1ed1i \u01b0u th\u1ef1c t\u1ebf g\u1eafn v\u1edbi \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1<\/span><\/td>\n<td><span data-path-to-node=\"4,3,5,0\"><b data-path-to-node=\"4,3,5,0\" data-index-in-node=\"0\">1.5 \u0111i\u1ec3m<\/b><\/span><\/td>\n<\/tr>\n<tr>\n<td><span data-path-to-node=\"4,4,0,0\"><b data-path-to-node=\"4,4,0,0\" data-index-in-node=\"0\">4. H\u1ec7 th\u1ee9c l\u01b0\u1ee3ng &amp; T\u1ec9 s\u1ed1 l\u01b0\u1ee3ng gi\u00e1c<\/b><\/span><\/td>\n<td><span data-path-to-node=\"4,4,1,0\">Thu\u1ed9c c\u00f4ng th\u1ee9c t\u1ec9 s\u1ed1 l\u01b0\u1ee3ng gi\u00e1c, h\u1ec7 th\u1ee9c trong tam gi\u00e1c vu\u00f4ng<\/span><\/td>\n<td><span data-path-to-node=\"4,4,2,0\">T\u00ednh c\u1ea1nh, g\u00f3c trong tam gi\u00e1c vu\u00f4ng; gi\u1ea3i tam gi\u00e1c vu\u00f4ng c\u01a1 b\u1ea3n<\/span><\/td>\n<td><span data-path-to-node=\"4,4,3,0\">B\u00e0i to\u00e1n th\u1ef1c t\u1ebf: \u0111o chi\u1ec1u cao t\u00f2a nh\u00e0, g\u00f3c n\u00e2ng, g\u00f3c h\u1ea1<\/span><\/td>\n<td><span data-path-to-node=\"4,4,4,0\">B\u00e0i to\u00e1n h\u00ecnh h\u1ecdc t\u1ed5ng h\u1ee3p, k\u1ebb th\u00eam \u0111\u01b0\u1eddng ph\u1ee5 ch\u1ee9ng minh \u0111\u1eb3ng th\u1ee9c<\/span><\/td>\n<td><span data-path-to-node=\"4,4,5,0\"><b data-path-to-node=\"4,4,5,0\" data-index-in-node=\"0\">3.0 \u2013 3.5 \u0111i\u1ec3m<\/b><\/span><\/td>\n<\/tr>\n<tr>\n<td><span data-path-to-node=\"4,5,0,0\"><b data-path-to-node=\"4,5,0,0\" data-index-in-node=\"0\">T\u1ed5ng t\u1ef7 l\u1ec7 \/ \u0110i\u1ec3m s\u1ed1<\/b><\/span><\/td>\n<td><span data-path-to-node=\"4,5,1,0\"><b data-path-to-node=\"4,5,1,0\" data-index-in-node=\"0\">3.0 \u0111i\u1ec3m (30%)<\/b><\/span><\/td>\n<td><span data-path-to-node=\"4,5,2,0\"><b data-path-to-node=\"4,5,2,0\" data-index-in-node=\"0\">3.0 \u0111i\u1ec3m (30%)<\/b><\/span><\/td>\n<td><span data-path-to-node=\"4,5,3,0\"><b data-path-to-node=\"4,5,3,0\" data-index-in-node=\"0\">3.0 \u0111i\u1ec3m (30%)<\/b><\/span><\/td>\n<td><span data-path-to-node=\"4,5,4,0\"><b data-path-to-node=\"4,5,4,0\" data-index-in-node=\"0\">1.0 \u0111i\u1ec3m (10%)<\/b><\/span><\/td>\n<td><span data-path-to-node=\"4,5,5,0\"><b data-path-to-node=\"4,5,5,0\" data-index-in-node=\"0\">10 \u0111i\u1ec3m (100%)<\/b><\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p data-path-to-node=\"2\"><!-- B\u1eaeT \u0110\u1ea6U PH\u1ea6N I: TR\u1eccNG T\u00c2M \u0110\u1ea0I S\u1ed0 GI\u1eeeA K\u00cc 1 TO\u00c1N 9 --><\/p>\n<div class=\"naviedu-content-section\" style=\"font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif; line-height: 1.8; color: #2d3748; font-size: 16px;\">\n<div style=\"background: linear-gradient(135deg, #0056b3, #0080ff); color: #ffffff; padding: 18px 24px; border-radius: 8px; margin-bottom: 30px;\">\n<h2 style=\"color: #ffffff; margin: 0; font-size: 22px; text-transform: uppercase; letter-spacing: 0.5px;\">Ph\u1ea7n I: Tr\u1ecdng T\u00e2m \u0110\u1ea1i S\u1ed1 Gi\u1eefa K\u1ef3 1 To\u00e1n 9<\/h2>\n<\/div>\n<p><!-- CH\u1ee6 \u0110\u1ec0 1 --><\/p>\n<h2 style=\"color: #0056b3; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; margin-top: 35px; font-size: 20px;\">1. Ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n<\/h2>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">1.1. L\u00fd thuy\u1ebft c\u1ed1t l\u00f5i &amp; \u0111i\u1ec1u ki\u1ec7n x\u00e1c \u0111\u1ecbnh<\/h3>\n<ul style=\"padding-left: 20px;\">\n<li><strong>Ph\u01b0\u01a1ng tr\u00ecnh t\u00edch:<\/strong> C\u00f3 d\u1ea1ng t\u1ed5ng qu\u00e1t <code>A(x) \u00b7 B(x) = 0<\/code> \u21d4 <strong>A(x) = 0<\/strong> ho\u1eb7c <strong>B(x) = 0<\/strong>.<\/li>\n<li><strong>Ph\u01b0\u01a1ng tr\u00ecnh ch\u1ee9a \u1ea9n \u1edf m\u1eabu:<\/strong>\n<ul>\n<li>B\u1eaft bu\u1ed9c ph\u1ea3i t\u00ecm <strong>\u0110i\u1ec1u ki\u1ec7n x\u00e1c \u0111\u1ecbnh (\u0110KX\u0110)<\/strong> b\u1eb1ng c\u00e1ch cho t\u1ea5t c\u1ea3 c\u00e1c m\u1eabu th\u1ee9c ch\u1ee9a \u1ea9n kh\u00e1c 0.<\/li>\n<li>Quy \u0111\u1ed3ng m\u1eabu th\u1ee9c hai v\u1ebf r\u1ed3i kh\u1eed m\u1eabu \u0111\u1ec3 \u0111\u01b0a v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t quen thu\u1ed9c.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">1.2. D\u1ea1ng b\u00e0i tr\u1ecdng t\u00e2m &amp; l\u1ed7i sai th\u01b0\u1eddng g\u1eb7p<\/h3>\n<ul style=\"padding-left: 20px;\">\n<li><strong style=\"color: #c53030;\">Qu\u00ean \u0111\u1ed1i chi\u1ebfu \u0110KX\u0110:<\/strong> H\u1ecdc sinh sau khi t\u00ecm ra nghi\u1ec7m th\u01b0\u1eddng v\u1ed9i v\u00e3 k\u1ebft lu\u1eadn m\u00e0 qu\u00ean so s\u00e1nh v\u1edbi \u0110KX\u0110 ban \u0111\u1ea7u, d\u1eabn \u0111\u1ebfn vi\u1ec7c nh\u1eadn c\u1ea3 nghi\u1ec7m ngo\u1ea1i lai (nghi\u1ec7m l\u00e0m cho m\u1eabu s\u1ed1 b\u1eb1ng 0).<\/li>\n<li><strong style=\"color: #c53030;\">T\u1ef1 \u00fd chia hai v\u1ebf cho bi\u1ec3u th\u1ee9c ch\u1ee9a \u1ea9n:<\/strong> V\u00ed d\u1ee5 khi g\u1eb7p <code>x(x - 2) = 3(x - 2)<\/code>, vi\u1ec7c chia c\u1ea3 hai v\u1ebf cho <code>(x - 2)<\/code> s\u1ebd l\u00e0m m\u1ea5t nghi\u1ec7m <code>x = 2<\/code>. Ph\u1ea3i lu\u00f4n chuy\u1ec3n v\u1ebf \u0111\u01b0a v\u1ec1 ph\u01b0\u01a1ng tr\u00ecnh t\u00edch: <code>(x - 2)(x - 3) = 0<\/code>.<\/li>\n<\/ul>\n<p><!-- V\u00cd D\u1ee4 M\u1eaaU 1 --><\/p>\n<div style=\"background-color: #f7fafc; border-left: 4px solid #0056b3; padding: 18px 20px; border-radius: 4px; margin: 20px 0;\">\n<p style=\"font-weight: bold; color: #0056b3; margin-top: 0; margin-bottom: 10px;\">V\u00ed d\u1ee5 m\u1eabu 1: Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh ch\u1ee9a \u1ea9n \u1edf m\u1eabu<\/p>\n<p style=\"margin-bottom: 10px;\"><strong>\u0110\u1ec1 b\u00e0i:<\/strong> Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh: <code>(x + 2)\/(x - 2) - 1\/x = 2\/[x(x - 2)]<\/code><\/p>\n<p style=\"margin-bottom: 6px;\"><strong>L\u1eddi gi\u1ea3i:<\/strong><\/p>\n<p style=\"margin: 4px 0;\">\u2022 <strong>\u0110KX\u0110:<\/strong> x \u2260 0 v\u00e0 x \u2260 2.<\/p>\n<p style=\"margin: 4px 0;\">\u2022 M\u1eabu th\u1ee9c chung: <code>x(x - 2)<\/code>. Quy \u0111\u1ed3ng hai v\u1ebf:<\/p>\n<p style=\"padding-left: 15px; margin: 6px 0; font-style: italic;\">[x(x + 2)] \/ [x(x &#8211; 2)] &#8211; (x &#8211; 2) \/ [x(x &#8211; 2)] = 2 \/ [x(x &#8211; 2)]<\/p>\n<p style=\"margin: 4px 0;\">\u2022 Kh\u1eed m\u1eabu th\u1ee9c v\u00e0 r\u00fat g\u1ecdn:<\/p>\n<p style=\"padding-left: 15px; margin: 6px 0;\">x(x + 2) &#8211; (x &#8211; 2) = 2<br \/>\n\u21d4 x<sup>2<\/sup> + 2x &#8211; x + 2 = 2<br \/>\n\u21d4 x<sup>2<\/sup> + x = 0<br \/>\n\u21d4 x(x + 1) = 0 \u21d4 x = 0 ho\u1eb7c x = -1<\/p>\n<p style=\"margin: 4px 0;\">\u2022 <strong>\u0110\u1ed1i chi\u1ebfu \u0110KX\u0110:<\/strong><\/p>\n<ul style=\"margin: 4px 0; padding-left: 20px;\">\n<li>x = 0 (Kh\u00f4ng th\u1ecfa m\u00e3n \u0110KX\u0110 &#8211; Lo\u1ea1i)<\/li>\n<li>x = -1 (Th\u1ecfa m\u00e3n \u0110KX\u0110 &#8211; Nh\u1eadn)<\/li>\n<\/ul>\n<p style=\"margin-top: 8px; margin-bottom: 0;\"><strong>K\u1ebft lu\u1eadn:<\/strong> V\u1eady t\u1eadp nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh l\u00e0 <strong>S = {-1}<\/strong>.<\/p>\n<\/div>\n<p><!-- CH\u1ee6 \u0110\u1ec0 2 --><\/p>\n<h2 style=\"color: #0056b3; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; margin-top: 35px; font-size: 20px;\">2. Ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t hai \u1ea9n<\/h2>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">2.1. Kh\u00e1i ni\u1ec7m &amp; bi\u1ec3u di\u1ec5n h\u00ecnh h\u1ecdc<\/h3>\n<ul style=\"padding-left: 20px;\">\n<li><strong>D\u1ea1ng t\u1ed5ng qu\u00e1t:<\/strong> <code>ax + by = c<\/code> v\u1edbi a, b, c l\u00e0 c\u00e1c s\u1ed1 \u0111\u00e3 bi\u1ebft v\u00e0 <strong>a<sup>2<\/sup> + b<sup>2<\/sup> \u2260 0<\/strong> (t\u1ee9c a v\u00e0 b kh\u00f4ng \u0111\u1ed3ng th\u1eddi b\u1eb1ng 0).<\/li>\n<li><strong>S\u1ed1 l\u01b0\u1ee3ng nghi\u1ec7m:<\/strong> Ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t hai \u1ea9n lu\u00f4n c\u00f3 <strong>v\u00f4 s\u1ed1 nghi\u1ec7m<\/strong> (x; y).<\/li>\n<li><strong>Bi\u1ec3u di\u1ec5n tr\u00ean m\u1eb7t ph\u1eb3ng Oxy:<\/strong> Trong m\u1eb7t ph\u1eb3ng t\u1ecda \u0111\u1ed9 Oxy, t\u1eadp nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh <code>ax + by = c<\/code> \u0111\u01b0\u1ee3c bi\u1ec3u di\u1ec5n b\u1edfi \u0111\u01b0\u1eddng th\u1eb3ng <code>(d): ax + by = c<\/code>.<\/li>\n<\/ul>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">2.2. D\u1ea1ng b\u00e0i tr\u1ecdng t\u00e2m<\/h3>\n<ul style=\"padding-left: 20px;\">\n<li><strong>X\u00e9t \u0111i\u1ec3m thu\u1ed9c \u0111\u01b0\u1eddng th\u1eb3ng:<\/strong> Thay t\u1ecda \u0111\u1ed9 \u0111i\u1ec3m M(x<sub>0<\/sub>; y<sub>0<\/sub>) v\u00e0o ph\u01b0\u01a1ng tr\u00ecnh. N\u1ebfu hai v\u1ebf b\u1eb1ng nhau th\u00ec \u0111i\u1ec3m M thu\u1ed9c \u0111\u01b0\u1eddng th\u1eb3ng.<\/li>\n<li><strong>T\u00ecm nghi\u1ec7m nguy\u00ean:<\/strong> Bi\u1ec3u di\u1ec5n \u1ea9n n\u00e0y theo \u1ea9n kia (v\u00ed d\u1ee5: r\u00fat <code>y = (c - ax)\/b<\/code>), s\u1eed d\u1ee5ng \u0111i\u1ec1u ki\u1ec7n chia h\u1ebft \u0111\u1ec3 t\u00ecm c\u00e1c gi\u00e1 tr\u1ecb x, y nguy\u00ean.<\/li>\n<\/ul>\n<p><!-- CH\u1ee6 \u0110\u1ec0 3 --><\/p>\n<h2 style=\"color: #0056b3; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; margin-top: 35px; font-size: 20px;\">3. Gi\u1ea3i h\u1ec7 hai ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t hai \u1ea9n<\/h2>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">3.1. Ph\u01b0\u01a1ng ph\u00e1p gi\u1ea3i c\u1ed1t l\u00f5i<\/h3>\n<p>H\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t hai \u1ea9n c\u00f3 d\u1ea1ng ti\u00eau chu\u1ea9n:<\/p>\n<div style=\"background: #edf2f7; padding: 10px 15px; border-radius: 6px; font-family: monospace; display: inline-block; margin-bottom: 12px;\">{ a<sub>1<\/sub>x + b<sub>1<\/sub>y = c<sub>1<\/sub><br \/>\n{ a<sub>2<\/sub>x + b<sub>2<\/sub>y = c<sub>2<\/sub><\/div>\n<ul style=\"padding-left: 20px;\">\n<li><strong>Ph\u01b0\u01a1ng ph\u00e1p th\u1ebf:<\/strong> Ph\u00f9 h\u1ee3p khi h\u1ec7 s\u1ed1 c\u1ee7a m\u1ed9t \u1ea9n l\u00e0 1 ho\u1eb7c -1. R\u00fat \u1ea9n \u0111\u00f3 ra r\u1ed3i th\u1ebf v\u00e0o ph\u01b0\u01a1ng tr\u00ecnh c\u00f2n l\u1ea1i.<\/li>\n<li><strong>Ph\u01b0\u01a1ng ph\u00e1p c\u1ed9ng \u0111\u1ea1i s\u1ed1:<\/strong> Nh\u00e2n c\u1ea3 hai v\u1ebf v\u1edbi s\u1ed1 th\u00edch h\u1ee3p \u0111\u1ec3 \u0111\u01b0a h\u1ec7 s\u1ed1 c\u1ee7a m\u1ed9t \u1ea9n v\u1ec1 d\u1ea1ng b\u1eb1ng nhau (th\u00ec tr\u1eeb) ho\u1eb7c \u0111\u1ed1i nhau (th\u00ec c\u1ed9ng) nh\u1eb1m tri\u1ec7t ti\u00eau \u1ea9n \u0111\u00f3.<\/li>\n<li><strong>Ph\u01b0\u01a1ng ph\u00e1p \u0111\u1eb7t \u1ea9n ph\u1ee5:<\/strong> \u00c1p d\u1ee5ng cho c\u00e1c h\u1ec7 ch\u1ee9a ph\u00e2n th\u1ee9c ho\u1eb7c ch\u1ee9a c\u0103n l\u1eb7p l\u1ea1i \u1edf c\u1ea3 hai ph\u01b0\u01a1ng tr\u00ecnh.<\/li>\n<\/ul>\n<p><!-- V\u00cd D\u1ee4 M\u1eaaU 2 --><\/p>\n<div style=\"background-color: #f7fafc; border-left: 4px solid #0056b3; padding: 18px 20px; border-radius: 4px; margin: 20px 0;\">\n<p style=\"font-weight: bold; color: #0056b3; margin-top: 0; margin-bottom: 10px;\">V\u00ed d\u1ee5 m\u1eabu 2: Gi\u1ea3i h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh b\u1eb1ng ph\u01b0\u01a1ng ph\u00e1p \u0111\u1eb7t \u1ea9n ph\u1ee5<\/p>\n<p style=\"margin-bottom: 6px;\"><strong>\u0110\u1ec1 b\u00e0i:<\/strong> Gi\u1ea3i h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh:<\/p>\n<div style=\"background: #ffffff; padding: 8px 12px; border: 1px solid #e2e8f0; border-radius: 4px; display: inline-block; margin-bottom: 10px; font-family: monospace;\">{ 2\/(x &#8211; 1) + 1\/(y + 2) = 5 \u00a0(1)<br \/>\n{ 3\/(x &#8211; 1) &#8211; 2\/(y + 2) = 4 \u00a0(2)<\/div>\n<p style=\"margin-bottom: 6px;\"><strong>L\u1eddi gi\u1ea3i:<\/strong><\/p>\n<p style=\"margin: 4px 0;\">\u2022 <strong>\u0110KX\u0110:<\/strong> x \u2260 1 v\u00e0 y \u2260 -2.<\/p>\n<p style=\"margin: 4px 0;\">\u2022 \u0110\u1eb7t: <code>u = 1\/(x - 1)<\/code> v\u00e0 <code>v = 1\/(y + 2)<\/code>. Khi \u0111\u00f3 h\u1ec7 tr\u1edf th\u00e0nh:<\/p>\n<p style=\"padding-left: 15px; margin: 6px 0; font-family: monospace;\">{ 2u + v = 5<br \/>\n{ 3u &#8211; 2v = 4<\/p>\n<p style=\"margin: 4px 0;\">\u2022 Nh\u00e2n 2 v\u00e0o ph\u01b0\u01a1ng tr\u00ecnh th\u1ee9 nh\u1ea5t: <code>4u + 2v = 10<\/code>. C\u1ed9ng t\u1eebng v\u1ebf v\u1edbi ph\u01b0\u01a1ng tr\u00ecnh th\u1ee9 hai:<\/p>\n<p style=\"padding-left: 15px; margin: 6px 0;\">(4u + 2v) + (3u &#8211; 2v) = 10 + 4<br \/>\n\u21d4 7u = 14 \u21d4 <strong>u = 2<\/strong><\/p>\n<p style=\"margin: 4px 0;\">\u2022 Thay u = 2 v\u00e0o <code>2u + v = 5<\/code> \u21d2 2(2) + v = 5 \u21d4 <strong>v = 1<\/strong>.<\/p>\n<p style=\"margin: 4px 0;\">\u2022 Tr\u1ea3 l\u1ea1i \u1ea9n x, y ban \u0111\u1ea7u:<\/p>\n<ul style=\"padding-left: 20px; margin: 4px 0;\">\n<li>1\/(x &#8211; 1) = 2 \u21d4 x &#8211; 1 = 1\/2 \u21d4 <strong>x = 3\/2<\/strong> (Th\u1ecfa m\u00e3n \u0110KX\u0110)<\/li>\n<li>1\/(y + 2) = 1 \u21d4 y + 2 = 1 \u21d4 <strong>y = -1<\/strong> (Th\u1ecfa m\u00e3n \u0110KX\u0110)<\/li>\n<\/ul>\n<p style=\"margin-top: 8px; margin-bottom: 0;\"><strong>K\u1ebft lu\u1eadn:<\/strong> H\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh c\u00f3 nghi\u1ec7m duy nh\u1ea5t <strong>(x; y) = (3\/2; -1)<\/strong>.<\/p>\n<\/div>\n<p><!-- CH\u1ee6 \u0110\u1ec0 4 --><\/p>\n<h2 style=\"color: #0056b3; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; margin-top: 35px; font-size: 20px;\">4. Gi\u1ea3i b\u00e0i to\u00e1n b\u1eb1ng c\u00e1ch l\u1eadp h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh<\/h2>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">4.1. Quy tr\u00ecnh 3 b\u01b0\u1edbc chu\u1ea9n<\/h3>\n<ol style=\"padding-left: 20px;\">\n<li><strong>B\u01b0\u1edbc 1: L\u1eadp h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh:<\/strong>\n<ul>\n<li>Ch\u1ecdn 2 \u1ea9n s\u1ed1 tr\u1ef1c ti\u1ebfp ho\u1eb7c gi\u00e1n ti\u1ebfp, \u0111\u1eb7t \u0111\u01a1n v\u1ecb \u0111o v\u00e0 \u0111i\u1ec1u ki\u1ec7n h\u1ee3p l\u00fd cho \u1ea9n (s\u1ed1 d\u01b0\u01a1ng, s\u1ed1 nguy\u00ean d\u01b0\u01a1ng,&#8230;).<\/li>\n<li>Bi\u1ec3u di\u1ec5n c\u00e1c \u0111\u1ea1i l\u01b0\u1ee3ng ch\u01b0a bi\u1ebft th\u00f4ng qua c\u00e1c \u1ea9n v\u00e0 \u0111\u1ea1i l\u01b0\u1ee3ng \u0111\u00e3 bi\u1ebft.<\/li>\n<li>D\u1ef1a v\u00e0o m\u1ed1i li\u00ean h\u1ec7 gi\u1eefa c\u00e1c \u0111\u1ea1i l\u01b0\u1ee3ng trong \u0111\u1ec1 b\u00e0i \u0111\u1ec3 l\u1eadp n\u00ean 2 ph\u01b0\u01a1ng tr\u00ecnh.<\/li>\n<\/ul>\n<\/li>\n<li><strong>B\u01b0\u1edbc 2: Gi\u1ea3i h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh:<\/strong> V\u1eadn d\u1ee5ng ph\u01b0\u01a1ng ph\u00e1p th\u1ebf ho\u1eb7c c\u1ed9ng \u0111\u1ea1i s\u1ed1.<\/li>\n<li><strong>B\u01b0\u1edbc 3: \u0110\u1ed1i chi\u1ebfu &amp; K\u1ebft lu\u1eadn:<\/strong> So s\u00e1nh nghi\u1ec7m t\u00ecm \u0111\u01b0\u1ee3c v\u1edbi \u0111i\u1ec1u ki\u1ec7n ban \u0111\u1ea7u \u0111\u1ec3 tr\u1ea3 l\u1eddi ch\u00ednh x\u00e1c c\u00e2u h\u1ecfi c\u1ee7a \u0111\u1ec1 b\u00e0i.<\/li>\n<\/ol>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">4.2. C\u00e1c d\u1ea1ng to\u00e1n th\u1ef1c t\u1ebf th\u01b0\u1eddng g\u1eb7p<\/h3>\n<div style=\"overflow-x: auto; margin: 15px 0;\">\n<table style=\"width: 100%; border-collapse: collapse; border: 1px solid #e2e8f0; text-align: left;\">\n<thead style=\"background-color: #f7fafc;\">\n<tr>\n<th style=\"padding: 10px 12px; border: 1px solid #cbd5e0; color: #0056b3;\">D\u1ea1ng b\u00e0i<\/th>\n<th style=\"padding: 10px 12px; border: 1px solid #cbd5e0; color: #0056b3;\">C\u00f4ng th\u1ee9c &amp; M\u1eb9o thi\u1ebft l\u1eadp ph\u01b0\u01a1ng tr\u00ecnh<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"padding: 10px 12px; border: 1px solid #cbd5e0; font-weight: bold;\">To\u00e1n chuy\u1ec3n \u0111\u1ed9ng<\/td>\n<td style=\"padding: 10px 12px; border: 1px solid #cbd5e0;\">\u2022 Qu\u00e3ng \u0111\u01b0\u1eddng = V\u1eadn t\u1ed1c \u00d7 Th\u1eddi gian (<code>S = v \u00b7 t<\/code>).<br \/>\n\u2022 D\u00f2ng n\u01b0\u1edbc: V<sub>xu\u00f4i<\/sub> = V<sub>th\u1ef1c<\/sub> + V<sub>d\u00f2ng n\u01b0\u1edbc<\/sub>; V<sub>ng\u01b0\u1ee3c<\/sub> = V<sub>th\u1ef1c<\/sub> &#8211; V<sub>d\u00f2ng n\u01b0\u1edbc<\/sub>.<\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 10px 12px; border: 1px solid #cbd5e0; font-weight: bold;\">N\u0103ng su\u1ea5t, l\u00e0m chung &#8211; l\u00e0m ri\u00eang<\/td>\n<td style=\"padding: 10px 12px; border: 1px solid #cbd5e0;\">\u2022 Coi to\u00e0n b\u1ed9 kh\u1ed1i l\u01b0\u1ee3ng c\u00f4ng vi\u1ec7c l\u00e0 <strong>1 \u0111\u01a1n v\u1ecb<\/strong>.<br \/>\n\u2022 N\u1ebfu ho\u00e0n th\u00e0nh xong trong x ng\u00e0y \u21d2 N\u0103ng su\u1ea5t 1 ng\u00e0y l\u00e0 <code>1\/x<\/code> c\u00f4ng vi\u1ec7c.<\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 10px 12px; border: 1px solid #cbd5e0; font-weight: bold;\">To\u00e1n kinh t\u1ebf &amp; Ph\u1ea7n tr\u0103m<\/td>\n<td style=\"padding: 10px 12px; border: 1px solid #cbd5e0;\">\u2022 Gi\u00e1 sau khi t\u0103ng k%: <code>A \u00b7 (1 + k%)<\/code>.<br \/>\n\u2022 Gi\u00e1 sau khi gi\u1ea3m k%: <code>A \u00b7 (1 - k%)<\/code>.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p><!-- CH\u1ee6 \u0110\u1ec0 5 --><\/p>\n<h2 style=\"color: #0056b3; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; margin-top: 35px; font-size: 20px;\">5. B\u1ea5t \u0111\u1eb3ng th\u1ee9c v\u00e0 t\u00ednh ch\u1ea5t<\/h2>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">5.1. Ki\u1ebfn th\u1ee9c c\u1ed1t l\u00f5i<\/h3>\n<ul style=\"padding-left: 20px;\">\n<li><strong>\u0110\u1ecbnh ngh\u0129a:<\/strong> V\u1edbi hai s\u1ed1 a v\u00e0 b b\u1ea5t k\u1ef3:\n<ul>\n<li><code>a &gt; b \u21d4 a - b &gt; 0<\/code><\/li>\n<li><code>a &lt; b \u21d4 a - b &lt; 0<\/code><\/li>\n<\/ul>\n<\/li>\n<li><strong>T\u00ednh ch\u1ea5t li\u00ean h\u1ec7 v\u1edbi ph\u00e9p to\u00e1n:<\/strong>\n<ul>\n<li><em>C\u1ed9ng:<\/em> a &lt; b \u21d4 a + c &lt; b + c.<\/li>\n<li><em>Nh\u00e2n s\u1ed1 d\u01b0\u01a1ng:<\/em> N\u1ebfu c &gt; 0 th\u00ec a &lt; b \u21d4 a \u00b7 c &lt; b \u00b7 c.<\/li>\n<li><em>Nh\u00e2n s\u1ed1 \u00e2m (\u0110\u1ed5i chi\u1ec1u):<\/em> N\u1ebfu c &lt; 0 th\u00ec a &lt; b \u21d4 <strong>a \u00b7 c &gt; b \u00b7 c<\/strong>.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">5.2. K\u1ef9 thu\u1eadt ch\u1ee9ng minh th\u01b0\u1eddng g\u1eb7p<\/h3>\n<ul style=\"padding-left: 20px;\">\n<li><strong>Ph\u01b0\u01a1ng ph\u00e1p x\u00e9t hi\u1ec7u:<\/strong> Mu\u1ed1n ch\u1ee9ng minh <code>A \u2265 B<\/code>, ta x\u00e9t hi\u1ec7u <code>A - B<\/code> r\u1ed3i bi\u1ebfn \u0111\u1ed5i v\u1ec1 d\u1ea1ng b\u00ecnh ph\u01b0\u01a1ng: <code>[f(x)]<sup>2<\/sup> \u2265 0<\/code>.<\/li>\n<li><strong>S\u1eed d\u1ee5ng h\u1eb1ng \u0111\u1eb3ng th\u1ee9c:<\/strong> Nh\u1edb r\u1eb1ng b\u00ecnh ph\u01b0\u01a1ng c\u1ee7a m\u1ecdi bi\u1ec3u th\u1ee9c lu\u00f4n kh\u00f4ng \u00e2m: <code>(a - b)<sup>2<\/sup> \u2265 0<\/code> v\u1edbi m\u1ecdi a, b. D\u1ea5u &#8220;=&#8221; x\u1ea3y ra khi a = b.<\/li>\n<\/ul>\n<p><!-- CH\u1ee6 \u0110\u1ec0 6 --><\/p>\n<h2 style=\"color: #0056b3; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; margin-top: 35px; font-size: 20px;\">6. B\u1ea5t ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n<\/h2>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">6.1. Kh\u00e1i ni\u1ec7m &amp; quy t\u1eafc bi\u1ebfn \u0111\u1ed5i<\/h3>\n<ul style=\"padding-left: 20px;\">\n<li><strong>D\u1ea1ng t\u1ed5ng qu\u00e1t:<\/strong> <code>ax + b &lt; 0<\/code> (ho\u1eb7c &gt;, \u2264, \u2265) v\u1edbi <strong>a \u2260 0<\/strong>.<\/li>\n<li><strong>Quy t\u1eafc chuy\u1ec3n v\u1ebf:<\/strong> Khi chuy\u1ec3n m\u1ed9t h\u1ea1ng t\u1eed t\u1eeb v\u1ebf n\u00e0y sang v\u1ebf kia ph\u1ea3i \u0111\u1ed5i d\u1ea5u h\u1ea1ng t\u1eed \u0111\u00f3.<\/li>\n<li><strong>Quy t\u1eafc nh\u00e2n\/chia:<\/strong> Khi nh\u00e2n ho\u1eb7c chia hai v\u1ebf c\u1ee7a b\u1ea5t ph\u01b0\u01a1ng tr\u00ecnh v\u1edbi m\u1ed9t s\u1ed1 \u00e2m, <strong>b\u1eaft bu\u1ed9c ph\u1ea3i \u0111\u1ed5i chi\u1ec1u<\/strong> c\u1ee7a b\u1ea5t ph\u01b0\u01a1ng tr\u00ecnh.<\/li>\n<\/ul>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">6.2. Bi\u1ec3u di\u1ec5n t\u1eadp nghi\u1ec7m tr\u00ean tr\u1ee5c s\u1ed1<\/h3>\n<ul style=\"padding-left: 20px;\">\n<li>D\u00f9ng <strong>ngo\u1eb7c tr\u00f2n <code>(<\/code> ho\u1eb7c <code>)<\/code><\/strong> cho c\u00e1c b\u1ea5t ph\u01b0\u01a1ng tr\u00ecnh ch\u1ee9a d\u1ea5u ng\u1eb7t (<code>&lt;<\/code> ho\u1eb7c <code>&gt;<\/code>).<\/li>\n<li>D\u00f9ng <strong>ngo\u1eb7c vu\u00f4ng <code>[<\/code> ho\u1eb7c <code>]<\/code><\/strong> cho c\u00e1c b\u1ea5t ph\u01b0\u01a1ng tr\u00ecnh ch\u1ee9a d\u1ea5u c\u00f3 d\u1ea5u b\u1eb1ng (<code>\u2264<\/code> ho\u1eb7c <code>\u2265<\/code>).<\/li>\n<\/ul>\n<p><!-- CH\u1ee6 \u0110\u1ec0 7 --><\/p>\n<h2 style=\"color: #0056b3; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; margin-top: 35px; font-size: 20px;\">7. X\u00e1c \u0111\u1ecbnh h\u00e0m s\u1ed1 b\u1eadc nh\u1ea5t y = ax + b<\/h2>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">7.1. \u0110\u1ecbnh ngh\u0129a &amp; t\u00ednh ch\u1ea5t bi\u1ebfn thi\u00ean<\/h3>\n<ul style=\"padding-left: 20px;\">\n<li>H\u00e0m s\u1ed1 b\u1eadc nh\u1ea5t c\u00f3 d\u1ea1ng <code>y = ax + b<\/code> (\u0111i\u1ec1u ki\u1ec7n: <strong>a \u2260 0<\/strong>).<\/li>\n<li><strong>T\u00ednh ch\u1ea5t bi\u1ebfn thi\u00ean:<\/strong>\n<ul>\n<li>H\u00e0m s\u1ed1 <strong>\u0111\u1ed3ng bi\u1ebfn<\/strong> tr\u00ean \u211d khi <strong>a &gt; 0<\/strong> (\u0111\u1ed3 th\u1ecb \u0111i l\u00ean t\u1eeb tr\u00e1i sang ph\u1ea3i).<\/li>\n<li>H\u00e0m s\u1ed1 <strong>ngh\u1ecbch bi\u1ebfn<\/strong> tr\u00ean \u211d khi <strong>a &lt; 0<\/strong> (\u0111\u1ed3 th\u1ecb \u0111i xu\u1ed1ng t\u1eeb tr\u00e1i sang ph\u1ea3i).<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">7.2. D\u1ea1ng b\u00e0i tr\u1ecdng t\u00e2m &amp; v\u1ecb tr\u00ed t\u01b0\u01a1ng \u0111\u1ed1i<\/h3>\n<ul style=\"padding-left: 20px;\">\n<li><strong>T\u00ecm h\u1ec7 s\u1ed1 a, b:<\/strong> Thay t\u1ecda \u0111\u1ed9 \u0111i\u1ec3m \u0111\u1ed3 th\u1ecb \u0111i qua v\u00e0o ph\u01b0\u01a1ng tr\u00ecnh \u0111\u1ec3 t\u00ecm a, b. L\u01b0u \u00fd giao \u0111i\u1ec3m v\u1edbi tr\u1ee5c tung l\u00e0 (0; b) v\u00e0 tr\u1ee5c ho\u00e0nh l\u00e0 (-b\/a; 0).<\/li>\n<li><strong>V\u1ecb tr\u00ed t\u01b0\u01a1ng \u0111\u1ed1i c\u1ee7a hai \u0111\u01b0\u1eddng th\u1eb3ng<\/strong> (d): y = ax + b v\u00e0 (d&#8217;): y = a&#8217;x + b&#8217; (v\u1edbi a, a&#8217; \u2260 0):\n<ul>\n<li><strong>(d) song song v\u1edbi (d&#8217;):<\/strong> \u21d4 a = a&#8217; v\u00e0 b \u2260 b&#8217;.<\/li>\n<li><strong>(d) tr\u00f9ng v\u1edbi (d&#8217;):<\/strong> \u21d4 a = a&#8217; v\u00e0 b = b&#8217;.<\/li>\n<li><strong>(d) c\u1eaft (d&#8217;):<\/strong> \u21d4 a \u2260 a&#8217;.<\/li>\n<li><em>(M\u1edf r\u1ed9ng) (d) vu\u00f4ng g\u00f3c v\u1edbi (d&#8217;):<\/em> \u21d4 a \u00b7 a&#8217; = -1.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/div>\n<p data-path-to-node=\"2\"><!-- B\u1eaeT \u0110\u1ea6U PH\u1ea6N II: TR\u1eccNG T\u00c2M H\u00ccNH H\u1eccC GI\u1eeeA K\u00cc 1 TO\u00c1N 9 --><\/p>\n<div class=\"naviedu-content-section\" style=\"font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif; line-height: 1.8; color: #2d3748; font-size: 16px;\">\n<div style=\"background: linear-gradient(135deg, #0056b3, #0080ff); color: #ffffff; padding: 18px 24px; border-radius: 8px; margin-bottom: 30px;\">\n<h2 style=\"color: #ffffff; margin: 0; font-size: 22px; text-transform: uppercase; letter-spacing: 0.5px;\">Ph\u1ea7n II: Tr\u1ecdng T\u00e2m H\u00ecnh H\u1ecdc Gi\u1eefa K\u1ef3 1 To\u00e1n 9<\/h2>\n<\/div>\n<p><!-- CH\u1ee6 \u0110\u1ec0 1 --><\/p>\n<h2 style=\"color: #0056b3; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; margin-top: 35px; font-size: 20px;\">1. T\u1ec9 s\u1ed1 l\u01b0\u1ee3ng gi\u00e1c c\u1ee7a g\u00f3c nh\u1ecdn<\/h2>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">1.1. \u0110\u1ecbnh ngh\u0129a &amp; m\u1eb9o ghi nh\u1edb nhanh<\/h3>\n<p>Cho tam gi\u00e1c ABC vu\u00f4ng t\u1ea1i A, x\u00e9t g\u00f3c nh\u1ecdn \u03b1 = \u2220B (v\u1edbi c\u1ea1nh \u0111\u1ed1i l\u00e0 AC, c\u1ea1nh k\u1ec1 l\u00e0 AB, c\u1ea1nh huy\u1ec1n l\u00e0 BC):<\/p>\n<ul style=\"padding-left: 20px;\">\n<li><strong>sin \u03b1<\/strong> = C\u1ea1nh \u0111\u1ed1i \/ C\u1ea1nh huy\u1ec1n = <code>AC \/ BC<\/code><\/li>\n<li><strong>cos \u03b1<\/strong> = C\u1ea1nh k\u1ec1 \/ C\u1ea1nh huy\u1ec1n = <code>AB \/ BC<\/code><\/li>\n<li><strong>tan \u03b1<\/strong> = C\u1ea1nh \u0111\u1ed1i \/ C\u1ea1nh k\u1ec1 = <code>AC \/ AB<\/code><\/li>\n<li><strong>cot \u03b1<\/strong> = C\u1ea1nh k\u1ec1 \/ C\u1ea1nh \u0111\u1ed1i = <code>AB \/ AC<\/code><\/li>\n<\/ul>\n<div style=\"background-color: #fffaf0; border-left: 4px solid #dd6b20; padding: 12px 18px; border-radius: 4px; margin: 15px 0;\">\n<p style=\"margin: 0; font-weight: bold; color: #c05621;\">M\u1eb9o ghi nh\u1edb b\u1eb1ng th\u01a1 c\u1ef1c d\u1ec5 thu\u1ed9c:<\/p>\n<p style=\"margin: 5px 0 0 0; font-style: italic;\">&#8220;<strong>Sao \u0110i H\u1ecdc<\/strong> (sin = \u0110\u1ed1i \/ Huy\u1ec1n)<br \/>\n<strong>C\u1ee9 Kh\u00f3c Ho\u00e0i<\/strong> (cos = K\u1ec1 \/ Huy\u1ec1n)<br \/>\n<strong>Th\u00f4i \u0110\u1eebng Kh\u00f3c<\/strong> (tan = \u0110\u1ed1i \/ K\u1ec1)<br \/>\n<strong>C\u00f3 K\u1eb9o \u0110\u00e2y<\/strong> (cot = K\u1ec1 \/ \u0110\u1ed1i)&#8221;<\/p>\n<\/div>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">1.2. T\u00ednh ch\u1ea5t b\u1ed5 tr\u1ee3 &amp; c\u00e1c h\u1ec7 th\u1ee9c quan tr\u1ecdng<\/h3>\n<ul style=\"padding-left: 20px;\">\n<li><strong>\u0110\u1ecbnh l\u00fd hai g\u00f3c ph\u1ee5 nhau:<\/strong> N\u1ebfu hai g\u00f3c ph\u1ee5 nhau (\u03b1 + \u03b2 = 90\u00b0) th\u00ec:\n<div style=\"background: #edf2f7; padding: 8px 14px; border-radius: 6px; margin: 8px 0; font-family: monospace;\">sin \u03b1 = cos \u03b2 \u00a0|\u00a0 cos \u03b1 = sin \u03b2<br \/>\ntan \u03b1 = cot \u03b2 \u00a0|\u00a0 cot \u03b1 = tan \u03b2<\/div>\n<p><em>(V\u00ed d\u1ee5: sin 30\u00b0 = cos 60\u00b0; tan 45\u00b0 = cot 45\u00b0 = 1; sin 75\u00b0 = cos 15\u00b0).<\/em><\/li>\n<li><strong>C\u00e1c h\u1ec7 th\u1ee9c l\u01b0\u1ee3ng gi\u00e1c c\u01a1 b\u1ea3n c\u1ea7n nh\u1edb:<\/strong>\n<ul>\n<li><code>sin<sup>2<\/sup>\u03b1 + cos<sup>2<\/sup>\u03b1 = 1<\/code><\/li>\n<li><code>tan \u03b1 = sin \u03b1 \/ cos \u03b1<\/code> (v\u1edbi cos \u03b1 \u2260 0)<\/li>\n<li><code>cot \u03b1 = cos \u03b1 \/ sin \u03b1<\/code> (v\u1edbi sin \u03b1 \u2260 0)<\/li>\n<li><code>tan \u03b1 \u00b7 cot \u03b1 = 1<\/code><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">1.3. D\u1ea1ng b\u00e0i t\u1eadp tr\u1ecdng t\u00e2m<\/h3>\n<ul style=\"padding-left: 20px;\">\n<li><strong>R\u00fat g\u1ecdn bi\u1ec3u th\u1ee9c kh\u00f4ng d\u00f9ng m\u00e1y t\u00ednh:<\/strong> V\u1eadn d\u1ee5ng t\u00ednh ch\u1ea5t hai g\u00f3c ph\u1ee5 nhau \u0111\u1ec3 tri\u1ec7t ti\u00eau c\u00e1c gi\u00e1 tr\u1ecb \u0111\u1ed1i x\u1ee9ng (v\u00ed d\u1ee5: bi\u1ebfn \u0111\u1ed5i <code>sin<sup>2<\/sup>20\u00b0 + sin<sup>2<\/sup>70\u00b0 = sin<sup>2<\/sup>20\u00b0 + cos<sup>2<\/sup>20\u00b0 = 1<\/code>).<\/li>\n<li><strong>Cho m\u1ed9t t\u1ec9 s\u1ed1 l\u01b0\u1ee3ng gi\u00e1c, t\u00ednh c\u00e1c t\u1ec9 s\u1ed1 c\u00f2n l\u1ea1i:<\/strong> S\u1eed d\u1ee5ng h\u1ec7 th\u1ee9c <code>sin<sup>2<\/sup>\u03b1 + cos<sup>2<\/sup>\u03b1 = 1<\/code> k\u1ebft h\u1ee3p \u0111\u1ecbnh ngh\u0129a tan, cot \u0111\u1ec3 t\u00ednh to\u00e1n chu\u1ea9n x\u00e1c m\u00e0 kh\u00f4ng c\u1ea7n t\u00ecm s\u1ed1 \u0111o g\u00f3c.<\/li>\n<\/ul>\n<p><!-- CH\u1ee6 \u0110\u1ec0 2 --><\/p>\n<h2 style=\"color: #0056b3; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; margin-top: 35px; font-size: 20px;\">2. H\u1ec7 th\u1ee9c gi\u1eefa c\u1ea1nh v\u00e0 g\u00f3c trong tam gi\u00e1c vu\u00f4ng<\/h2>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">2.1. C\u00e1c c\u00f4ng th\u1ee9c chu\u1ea9n<\/h3>\n<p>Trong tam gi\u00e1c vu\u00f4ng ABC (vu\u00f4ng t\u1ea1i A, c\u1ea1nh huy\u1ec1n a = BC, c\u00e1c c\u1ea1nh g\u00f3c vu\u00f4ng b = AC, c = AB):<\/p>\n<div style=\"overflow-x: auto; margin: 15px 0;\">\n<table style=\"width: 100%; border-collapse: collapse; border: 1px solid #e2e8f0; text-align: left;\">\n<thead style=\"background-color: #f7fafc;\">\n<tr>\n<th style=\"padding: 10px 14px; border: 1px solid #cbd5e0; color: #0056b3;\">Quy t\u1eafc ph\u00e1t bi\u1ec3u<\/th>\n<th style=\"padding: 10px 14px; border: 1px solid #cbd5e0; color: #0056b3;\">C\u00f4ng th\u1ee9c to\u00e1n h\u1ecdc<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"padding: 10px 14px; border: 1px solid #cbd5e0;\">M\u1ed7i c\u1ea1nh g\u00f3c vu\u00f4ng b\u1eb1ng <strong>c\u1ea1nh huy\u1ec1n<\/strong> nh\u00e2n v\u1edbi <strong>sin g\u00f3c \u0111\u1ed1i<\/strong> ho\u1eb7c nh\u00e2n v\u1edbi <strong>cos g\u00f3c k\u1ec1<\/strong>.<\/td>\n<td style=\"padding: 10px 14px; border: 1px solid #cbd5e0; font-family: monospace;\">b = a \u00b7 sin B = a \u00b7 cos C<br \/>\nc = a \u00b7 sin C = a \u00b7 cos B<\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 10px 14px; border: 1px solid #cbd5e0;\">M\u1ed7i c\u1ea1nh g\u00f3c vu\u00f4ng b\u1eb1ng <strong>c\u1ea1nh g\u00f3c vu\u00f4ng kia<\/strong> nh\u00e2n v\u1edbi <strong>tan g\u00f3c \u0111\u1ed1i<\/strong> ho\u1eb7c nh\u00e2n v\u1edbi <strong>cot g\u00f3c k\u1ec1<\/strong>.<\/td>\n<td style=\"padding: 10px 14px; border: 1px solid #cbd5e0; font-family: monospace;\">b = c \u00b7 tan B = c \u00b7 cot C<br \/>\nc = b \u00b7 tan C = b \u00b7 cot B<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">2.2. \u1ee8ng d\u1ee5ng to\u00e1n h\u1ecdc v\u00e0o \u0111\u1eddi s\u1ed1ng th\u1ef1c t\u1ebf<\/h3>\n<p>\u0110\u1ec1 thi gi\u1eefa k\u1ef3 1 To\u00e1n 9 hi\u1ec7n nay lu\u00f4n d\u00e0nh t\u1eeb <strong>1.0 \u0111\u1ebfn 1.5 \u0111i\u1ec3m<\/strong> cho b\u00e0i to\u00e1n h\u00ecnh h\u1ecdc th\u1ef1c t\u1ebf. C\u00e1c m\u00f4 h\u00ecnh quen thu\u1ed9c g\u1ed3m c\u00f3:<\/p>\n<ul style=\"padding-left: 20px;\">\n<li><strong>\u0110o chi\u1ec1u cao v\u1eadt th\u1ec3 kh\u00f4ng t\u1edbi \u0111\u01b0\u1ee3c \u0111\u1ec9nh:<\/strong> Chi\u1ec1u cao t\u00f2a nh\u00e0, th\u00e1p truy\u1ec1n h\u00ecnh, c\u00e2y xanh ho\u1eb7c b\u00f3ng c\u1ed9t c\u1edd in tr\u00ean m\u1eb7t \u0111\u1ea5t (s\u1eed d\u1ee5ng g\u00f3c n\u00e2ng c\u1ee7a tia n\u1eafng m\u1eb7t tr\u1eddi v\u00e0 c\u00f4ng th\u1ee9c <code>h = d \u00b7 tan \u03b1<\/code>).<\/li>\n<li><strong>\u0110o kho\u1ea3ng c\u00e1ch kh\u00f4ng \u0111o tr\u1ef1c ti\u1ebfp \u0111\u01b0\u1ee3c:<\/strong> Chi\u1ec1u r\u1ed9ng kh\u00fac s\u00f4ng, kho\u1ea3ng c\u00e1ch gi\u1eefa hai con thuy\u1ec1n tr\u00ean bi\u1ec3n b\u1eb1ng c\u00e1ch \u0111o g\u00f3c ng\u1eafm t\u1eeb \u0111\u00e0i quan s\u00e1t ho\u1eb7c h\u1ea3i \u0111\u0103ng.<\/li>\n<\/ul>\n<p><!-- V\u00cd D\u1ee4 TH\u1ef0C T\u1ebe --><\/p>\n<div style=\"background-color: #f7fafc; border-left: 4px solid #0056b3; padding: 18px 20px; border-radius: 4px; margin: 20px 0;\">\n<p style=\"font-weight: bold; color: #0056b3; margin-top: 0; margin-bottom: 8px;\">V\u00ed d\u1ee5 th\u1ef1c t\u1ebf: B\u00e0i to\u00e1n t\u00ednh chi\u1ec1u cao t\u00f2a nh\u00e0<\/p>\n<p style=\"margin-bottom: 8px;\"><strong>\u0110\u1ec1 b\u00e0i:<\/strong> M\u1ed9t ng\u01b0\u1eddi \u0111\u1ee9ng c\u00e1ch ch\u00e2n t\u00f2a nh\u00e0 m\u1ed9t kho\u1ea3ng d = 30 m. Ng\u01b0\u1eddi \u0111\u00f3 nh\u00ecn l\u00ean \u0111\u1ec9nh t\u00f2a nh\u00e0 v\u1edbi m\u1ed9t g\u00f3c n\u00e2ng 40\u00b0. Bi\u1ebft t\u1ea7m m\u1eaft c\u1ee7a ng\u01b0\u1eddi \u0111\u00f3 c\u00e1ch m\u1eb7t \u0111\u1ea5t 1.6 m. T\u00ednh chi\u1ec1u cao c\u1ee7a t\u00f2a nh\u00e0 (l\u00e0m tr\u00f2n \u0111\u1ebfn ch\u1eef s\u1ed1 th\u1eadp ph\u00e2n th\u1ee9 nh\u1ea5t).<\/p>\n<p style=\"margin-bottom: 6px;\"><strong>L\u1eddi gi\u1ea3i:<\/strong><\/p>\n<p style=\"margin: 4px 0;\">\u2022 G\u1ecdi h<sub>1<\/sub> l\u00e0 kho\u1ea3ng c\u00e1ch t\u1eeb t\u1ea7m m\u1eaft \u0111\u1ebfn \u0111\u1ec9nh t\u00f2a nh\u00e0. \u00c1p d\u1ee5ng h\u1ec7 th\u1ee9c c\u1ea1nh v\u00e0 g\u00f3c trong tam gi\u00e1c vu\u00f4ng:<\/p>\n<p style=\"padding-left: 15px; margin: 6px 0; font-family: monospace;\">h<sub>1<\/sub> = 30 \u00b7 tan 40\u00b0 \u2248 30 \u00b7 0.8391 \u2248 25.17 (m)<\/p>\n<p style=\"margin: 4px 0;\">\u2022 Chi\u1ec1u cao th\u1ef1c t\u1ebf c\u1ee7a t\u00f2a nh\u00e0 l\u00e0:<\/p>\n<p style=\"padding-left: 15px; margin: 6px 0; font-family: monospace;\">H = h<sub>1<\/sub> + 1.6 = 25.17 + 1.6 \u2248 26.8 (m)<\/p>\n<p style=\"margin-top: 6px; margin-bottom: 0;\"><strong>K\u1ebft lu\u1eadn:<\/strong> Chi\u1ec1u cao c\u1ee7a t\u00f2a nh\u00e0 x\u1ea5p x\u1ec9 <strong>26.8 m\u00e9t<\/strong>.<\/p>\n<\/div>\n<p><!-- CH\u1ee6 \u0110\u1ec0 3 --><\/p>\n<h2 style=\"color: #0056b3; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; margin-top: 35px; font-size: 20px;\">3. Gi\u1ea3i tam gi\u00e1c vu\u00f4ng<\/h2>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">3.1. B\u1ea3n ch\u1ea5t c\u1ee7a b\u00e0i to\u00e1n gi\u1ea3i tam gi\u00e1c vu\u00f4ng<\/h3>\n<ul style=\"padding-left: 20px;\">\n<li><strong>Kh\u00e1i ni\u1ec7m:<\/strong> &#8220;Gi\u1ea3i tam gi\u00e1c vu\u00f4ng&#8221; l\u00e0 b\u00e0i to\u00e1n t\u00ecm t\u1ea5t c\u1ea3 c\u00e1c c\u1ea1nh v\u00e0 c\u00e1c g\u00f3c ch\u01b0a bi\u1ebft c\u1ee7a tam gi\u00e1c khi \u0111\u00e3 bi\u1ebft tr\u01b0\u1edbc <strong>2 y\u1ebfu t\u1ed1<\/strong> (trong \u0111\u00f3 b\u1eaft bu\u1ed9c ph\u1ea3i c\u00f3 <strong>\u00edt nh\u1ea5t 1 c\u1ea1nh<\/strong>).<\/li>\n<li><strong>Hai tr\u01b0\u1eddng h\u1ee3p c\u01a1 b\u1ea3n:<\/strong>\n<ul>\n<li>Bi\u1ebft 1 c\u1ea1nh huy\u1ec1n v\u00e0 1 g\u00f3c nh\u1ecdn (ho\u1eb7c 1 c\u1ea1nh g\u00f3c vu\u00f4ng v\u00e0 1 g\u00f3c nh\u1ecdn).<\/li>\n<li>Bi\u1ebft 2 c\u1ea1nh (2 c\u1ea1nh g\u00f3c vu\u00f4ng ho\u1eb7c 1 c\u1ea1nh huy\u1ec1n v\u00e0 1 c\u1ea1nh g\u00f3c vu\u00f4ng).<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 20px;\">3.2. Ph\u01b0\u01a1ng ph\u00e1p t\u1ed1i \u01b0u s\u1ed1 b\u01b0\u1edbc t\u00ednh<\/h3>\n<ol style=\"padding-left: 20px;\">\n<li><strong>B\u01b0\u1edbc 1 (T\u00ednh g\u00f3c):<\/strong> N\u1ebfu bi\u1ebft 1 g\u00f3c nh\u1ecdn \u03b1, t\u00ednh ngay g\u00f3c nh\u1ecdn c\u00f2n l\u1ea1i qua c\u00f4ng th\u1ee9c: <code>\u03b2 = 90\u00b0 - \u03b1<\/code>.<\/li>\n<li><strong>B\u01b0\u1edbc 2 (T\u00ednh c\u1ea1nh):<\/strong>\n<ul>\n<li>N\u1ebfu bi\u1ebft 2 c\u1ea1nh: \u01afu ti\u00ean d\u00f9ng <strong>\u0111\u1ecbnh l\u00fd Pythagore<\/strong> (<code>a<sup>2<\/sup> = b<sup>2<\/sup> + c<sup>2<\/sup><\/code>) \u0111\u1ec3 t\u00ecm c\u1ea1nh c\u00f2n l\u1ea1i nhanh nh\u1ea5t v\u00e0 chu\u1ea9n x\u00e1c nh\u1ea5t.<\/li>\n<li>N\u1ebfu bi\u1ebft 1 c\u1ea1nh v\u00e0 1 g\u00f3c: D\u00f9ng tr\u1ef1c ti\u1ebfp h\u1ec7 th\u1ee9c gi\u1eefa c\u1ea1nh v\u00e0 g\u00f3c (sin, cos ho\u1eb7c tan) \u0111\u1ec3 t\u00ecm \u0111\u1ed9 d\u00e0i c\u1ea1nh ch\u01b0a bi\u1ebft.<\/li>\n<\/ul>\n<\/li>\n<li><strong>B\u01b0\u1edbc 3 (Ki\u1ec3m tra &amp; L\u00e0m tr\u00f2n):<\/strong> Ch\u00fa \u00fd quy chu\u1ea9n l\u00e0m tr\u00f2n \u0111\u1ed9 d\u00e0i c\u1ea1nh (th\u01b0\u1eddng l\u00e0 h\u00e0ng th\u1eadp ph\u00e2n th\u1ee9 nh\u1ea5t ho\u1eb7c th\u1ee9 hai) v\u00e0 s\u1ed1 \u0111o g\u00f3c (l\u00e0m tr\u00f2n \u0111\u1ebfn \u0111\u1ed9 ho\u1eb7c ph\u00fat) theo \u0111\u00fang y\u00eau c\u1ea7u \u0111\u1ec1 b\u00e0i.<\/li>\n<\/ol>\n<p><!-- INTERNAL LINK BOX --><\/p>\n<div style=\"background-color: #edf2f7; border-left: 4px solid #4a5568; padding: 14px 18px; border-radius: 4px; margin-top: 25px;\">\n<p style=\"margin: 0; font-size: 15px; color: #2d3748;\"><strong>* L\u01b0u \u00fd \u00f4n t\u1eadp:<\/strong> Ph\u1ea7n h\u00ecnh h\u1ecdc chi\u1ebfm t\u1eeb 3.0 \u0111\u1ebfn 3.5 \u0111i\u1ec3m nh\u01b0ng l\u00e0 ph\u1ea7n h\u1ecdc sinh d\u1ec5 m\u1ea5t \u0111i\u1ec3m oan nh\u1ea5t do v\u1ebd sai h\u00ecnh ho\u1eb7c qu\u00ean c\u00f4ng th\u1ee9c l\u01b0\u1ee3ng gi\u00e1c. N\u1ebfu con \u0111ang b\u1ecb h\u1ed5ng ki\u1ebfn th\u1ee9c t\u1eeb c\u00e1c l\u1edbp d\u01b0\u1edbi v\u00e0 l\u00fang t\u00fang khi v\u1ebd h\u00ecnh, ph\u1ee5 huynh n\u00ean tham kh\u1ea3o ngay gi\u1ea3i ph\u00e1p <span style=\"text-decoration: underline;\"><strong>l\u1ea5y l\u1ea1i g\u1ed1c To\u00e1n 9<\/strong><\/span> \u0111\u1ec3 k\u1ecbp th\u1eddi c\u1ee7ng c\u1ed1 k\u1ef9 n\u0103ng l\u1eadp lu\u1eadn tr\u01b0\u1edbc khi b\u01b0\u1edbc v\u00e0o k\u1ef3 thi ch\u00ednh th\u1ee9c.<\/p>\n<\/div>\n<\/div>\n<p data-path-to-node=\"2\"><!-- B\u1eaeT \u0110\u1ea6U PH\u1ea6N III: K\u1ebe HO\u1ea0CH H\u00c0NH \u0110\u1ed8NG & \u0110\u1ec0 THI M\u1eaaU --><\/p>\n<div class=\"naviedu-content-section\" style=\"font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif; line-height: 1.8; color: #2d3748; font-size: 16px;\">\n<div style=\"background: linear-gradient(135deg, #0056b3, #0080ff); color: #ffffff; padding: 18px 24px; border-radius: 8px; margin-bottom: 30px;\">\n<h2 style=\"color: #ffffff; margin: 0; font-size: 22px; text-transform: uppercase; letter-spacing: 0.5px;\">Ph\u1ea7n III: K\u1ebf Ho\u1ea1ch H\u00e0nh \u0110\u1ed9ng &amp; \u0110\u1ec1 Thi M\u1eabu<\/h2>\n<\/div>\n<p><!-- CH\u1ee6 \u0110\u1ec0 1 --><\/p>\n<h2 style=\"color: #0056b3; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; margin-top: 35px; font-size: 20px;\">L\u1ed9 tr\u00ecnh 7 ng\u00e0y \u00f4n t\u1eadp gi\u1eefa k\u1ef3 1 To\u00e1n 9 n\u01b0\u1edbc r\u00fat \u0111\u1ea1t \u0111i\u1ec3m 8+<\/h2>\n<p>\u0110\u1ec3 \u0111\u1ea1t \u0111i\u1ec3m s\u1ed1 t\u1ed1i \u01b0u trong giai \u0111o\u1ea1n n\u01b0\u1edbc r\u00fat, h\u1ecdc sinh kh\u00f4ng n\u00ean \u00f4n t\u1eadp d\u00e0n tr\u1ea3i hay l\u00e0m \u0111\u1ec1 m\u1ed9t c\u00e1ch t\u00f9y h\u1ee9ng. M\u1ed9t k\u1ebf ho\u1ea1ch ph\u00e2n b\u1ed5 th\u1eddi gian khoa h\u1ecdc trong v\u00f2ng 1 tu\u1ea7n s\u1ebd gi\u00fap c\u00e1c em c\u1ee7ng c\u1ed1 to\u00e0n di\u1ec7n l\u1ed7 h\u1ed5ng v\u00e0 \u0111\u1ea1t phong \u0111\u1ed9 thi c\u1eed t\u1ed1t nh\u1ea5t.<\/p>\n<div style=\"overflow-x: auto; margin: 20px 0;\">\n<table style=\"width: 100%; border-collapse: collapse; border: 1px solid #e2e8f0; text-align: left;\">\n<thead style=\"background-color: #f7fafc;\">\n<tr>\n<th style=\"padding: 12px 14px; border: 1px solid #cbd5e0; color: #0056b3; width: 22%;\">Th\u1eddi gian<\/th>\n<th style=\"padding: 12px 14px; border: 1px solid #cbd5e0; color: #0056b3; width: 43%;\">N\u1ed9i dung tr\u1ecdng t\u00e2m<\/th>\n<th style=\"padding: 12px 14px; border: 1px solid #cbd5e0; color: #0056b3; width: 35%;\">M\u1ee5c ti\u00eau c\u1ea7n \u0111\u1ea1t<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0; font-weight: bold;\">Ng\u00e0y 1 \u2013 2<\/td>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0;\">\u2022 R\u00e0 so\u00e1t l\u00fd thuy\u1ebft \u0110\u1ea1i s\u1ed1 c\u1ed1t l\u00f5i.<br \/>\n\u2022 Luy\u1ec7n ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n (ph\u01b0\u01a1ng tr\u00ecnh t\u00edch, ch\u1ee9a \u1ea9n \u1edf m\u1eabu).<br \/>\n\u2022 Th\u00e0nh th\u1ea1o ph\u01b0\u01a1ng ph\u00e1p th\u1ebf, c\u1ed9ng \u0111\u1ea1i s\u1ed1 v\u00e0 \u0111\u1eb7t \u1ea9n ph\u1ee5 \u0111\u1ec3 gi\u1ea3i h\u1ec7 hai ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t hai \u1ea9n.<\/td>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0;\">X\u1eed l\u00fd chu\u1ea9n x\u00e1c 100% \u0110KX\u0110, kh\u00f4ng nh\u1ea7m d\u1ea5u, \u0111\u1ea1t tr\u1ecdn v\u1eb9n \u0111i\u1ec3m ph\u1ea7n t\u00ednh to\u00e1n c\u01a1 b\u1ea3n.<\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0; font-weight: bold;\">Ng\u00e0y 3<\/td>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0;\">\u2022 Luy\u1ec7n chuy\u00ean \u0111\u1ec1 gi\u1ea3i b\u00e0i to\u00e1n b\u1eb1ng c\u00e1ch l\u1eadp h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh.<br \/>\n\u2022 T\u1eadp trung v\u00e0o 3 d\u1ea1ng then ch\u1ed1t: chuy\u1ec3n \u0111\u1ed9ng (xu\u00f4i\/ng\u01b0\u1ee3c d\u00f2ng), n\u0103ng su\u1ea5t (l\u00e0m chung &#8211; l\u00e0m ri\u00eang) v\u00e0 to\u00e1n kinh t\u1ebf\/ph\u1ea7n tr\u0103m.<\/td>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0;\">Bi\u1ebft c\u00e1ch l\u1eadp b\u1ea3ng ph\u00e2n t\u00edch d\u1eef ki\u1ec7n, ch\u1ecdn \u1ea9n, \u0111\u1eb7t \u0111i\u1ec1u ki\u1ec7n chu\u1ea9n v\u00e0 \u0111\u1ed1i chi\u1ebfu k\u1ebft lu\u1eadn.<\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0; font-weight: bold;\">Ng\u00e0y 4<\/td>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0;\">\u2022 T\u1ed5ng \u00f4n B\u1ea5t \u0111\u1eb3ng th\u1ee9c &amp; t\u00ednh ch\u1ea5t li\u00ean quan \u0111\u1ebfn ph\u00e9p to\u00e1n.<br \/>\n\u2022 Gi\u1ea3i b\u1ea5t ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n v\u00e0 bi\u1ec3u di\u1ec5n t\u1eadp nghi\u1ec7m tr\u00ean tr\u1ee5c s\u1ed1.<br \/>\n\u2022 H\u00e0m s\u1ed1 b\u1eadc nh\u1ea5t: t\u00ednh \u0111\u1ed3ng bi\u1ebfn\/ngh\u1ecbch bi\u1ebfn, t\u00ecm h\u1ec7 s\u1ed1 a, b v\u00e0 x\u00e9t v\u1ecb tr\u00ed t\u01b0\u01a1ng \u0111\u1ed1i gi\u1eefa hai \u0111\u01b0\u1eddng th\u1eb3ng.<\/td>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0;\">Kh\u00f4ng nh\u1ea7m quy t\u1eafc \u0111\u1ed5i chi\u1ec1u khi nh\u00e2n\/chia s\u1ed1 \u00e2m; nh\u1edb \u0111i\u1ec1u ki\u1ec7n song song, c\u1eaft nhau c\u1ee7a \u0111\u1ed3 th\u1ecb.<\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0; font-weight: bold;\">Ng\u00e0y 5<\/td>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0;\">\u2022 T\u1ed5ng \u00f4n to\u00e0n b\u1ed9 H\u00ecnh h\u1ecdc: \u0111\u1ecbnh ngh\u0129a t\u1ec9 s\u1ed1 l\u01b0\u1ee3ng gi\u00e1c, h\u1ec7 th\u1ee9c g\u00f3c ph\u1ee5 nhau.<br \/>\n\u2022 H\u1ec7 th\u1ee9c gi\u1eefa c\u1ea1nh v\u00e0 g\u00f3c trong tam gi\u00e1c vu\u00f4ng &amp; gi\u1ea3i tam gi\u00e1c vu\u00f4ng.<br \/>\n\u2022 Luy\u1ec7n gi\u1ea3i 5\u20137 b\u00e0i to\u00e1n \u1ee9ng d\u1ee5ng th\u1ef1c t\u1ebf (\u0111o chi\u1ec1u cao, kho\u1ea3ng c\u00e1ch s\u00f4ng).<\/td>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0;\">V\u1ebd h\u00ecnh chu\u1ea9n x\u00e1c, vi\u1ebft \u0111\u00fang t\u1ec9 s\u1ed1 l\u01b0\u1ee3ng gi\u00e1c theo c\u1ea1nh, l\u00e0m tr\u00f2n s\u1ed1 \u0111o c\u1ea1nh\/g\u00f3c \u0111\u00fang quy \u0111\u1ecbnh \u0111\u1ec1 b\u00e0i.<\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0; font-weight: bold;\">Ng\u00e0y 6<\/td>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0;\">\u2022 L\u00e0m th\u1eed 2 \u0111\u1ec1 thi m\u1eabu chu\u1ea9n c\u1ea5u tr\u00fac gi\u1eefa k\u1ef3 1.<br \/>\n\u2022 B\u1ea5m gi\u1edd nghi\u00eam t\u00fac 90 ph\u00fat\/\u0111\u1ec1, t\u1ea1o \u00e1p l\u1ef1c nh\u01b0 thi th\u1eadt.<br \/>\n\u2022 T\u1ef1 ch\u1ea5m \u0111i\u1ec3m, l\u1eadp b\u1ea3ng \u0111\u1ed1i chi\u1ebfu \u0111\u00e1p \u00e1n chi ti\u1ebft.<\/td>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0;\">\u0110\u00e1nh gi\u00e1 ch\u00ednh x\u00e1c t\u1ed1c \u0111\u1ed9 l\u00e0m b\u00e0i, nh\u1eadn di\u1ec7n c\u00e1c b\u1eaby \u0111\u1ec1 thi v\u00e0 qu\u1ea3n l\u00fd ph\u00e2n b\u1ed5 th\u1eddi gian.<\/td>\n<\/tr>\n<tr>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0; font-weight: bold;\">Ng\u00e0y 7<\/td>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0;\">\u2022 R\u00e0 so\u00e1t l\u1ea1i to\u00e0n b\u1ed9 &#8220;s\u1ed5 tay l\u1ed7i sai&#8221; t\u1eeb c\u00e1c ng\u00e0y tr\u01b0\u1edbc.<br \/>\n\u2022 Kh\u00f4ng nh\u1ed3i nh\u00e9t \u0111\u1ec1 m\u1edbi ph\u1ee9c t\u1ea1p.<br \/>\n\u2022 Chu\u1ea9n b\u1ecb \u0111\u1ea7y \u0111\u1ee7 d\u1ee5ng c\u1ee5 h\u1ecdc t\u1eadp (m\u00e1y t\u00ednh, th\u01b0\u1edbc k\u1ebb, compa), \u0111i ng\u1ee7 s\u1edbm \u0111\u1ec3 gi\u1eef tinh th\u1ea7n minh m\u1eabn.<\/td>\n<td style=\"padding: 12px 14px; border: 1px solid #cbd5e0;\">Kh\u1eafc s\u00e2u c\u00e1c l\u1ed7i sai kinh \u0111i\u1ec3n \u0111\u1ec3 kh\u00f4ng t\u00e1i ph\u1ea1m; \u1ed5n \u0111\u1ecbnh t\u00e2m l\u00fd t\u1ef1 tin tr\u01b0\u1edbc gi\u1edd thi.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<div style=\"background-color: #edf2f7; border-left: 4px solid #0056b3; padding: 14px 18px; border-radius: 4px; margin: 20px 0;\">\n<p style=\"margin: 0; font-size: 15px; color: #2d3748;\"><strong>G\u1ee3i \u00fd h\u1eefu \u00edch:<\/strong> B\u00ean c\u1ea1nh vi\u1ec7c b\u00e1m s\u00e1t k\u1ebf ho\u1ea1ch \u00f4n t\u1eadp, ba m\u1eb9 v\u00e0 c\u00e1c em h\u1ecdc sinh c\u00f3 th\u1ec3 tham kh\u1ea3o th\u00eam c\u00e1c <a style=\"color: #0056b3; font-weight: bold; text-decoration: underline;\" href=\"https:\/\/navi.edu.vn\/blog\/blog\/toan-lop-9\/\">kinh nghi\u1ec7m h\u1ecdc To\u00e1n 9<\/a> \u0111\u1ec3 trang b\u1ecb c\u00e1c m\u1eb9o l\u00e0m b\u00e0i tr\u1eafc nghi\u1ec7m nhanh, k\u1ef9 n\u0103ng tr\u00ecnh b\u00e0y b\u00e0i t\u1ef1 lu\u1eadn kh\u00f4ng b\u1ecb tr\u1eeb \u0111i\u1ec3m v\u1eb7t v\u00e0 ph\u01b0\u01a1ng ph\u00e1p gi\u1eef v\u1eefng t\u00e2m l\u00fd ph\u00f2ng thi.<\/p>\n<\/div>\n<p><!-- CH\u1ee6 \u0110\u1ec0 2 --><\/p>\n<h2 style=\"color: #0056b3; border-bottom: 2px solid #e2e8f0; padding-bottom: 8px; margin-top: 35px; font-size: 20px;\">T\u1ea3i tr\u1ecdn b\u1ed9 \u0111\u1ec1 c\u01b0\u01a1ng v\u00e0 \u0111\u1ec1 thi m\u1eabu gi\u1eefa k\u1ef3 1 To\u00e1n 9 (K\u00e8m \u0111\u00e1p \u00e1n chi ti\u1ebft)<\/h2>\n<p>Nh\u1eb1m gi\u00fap h\u1ecdc sinh l\u00e0m quen v\u1edbi c\u1ea5u tr\u00fac \u0111\u1ec1 thi ch\u00ednh th\u1ee9c theo ch\u01b0\u01a1ng tr\u00ecnh GDPT m\u1edbi, ban chuy\u00ean m\u00f4n t\u1ea1i NaviEdu \u0111\u00e3 bi\u00ean so\u1ea1n b\u1ed9 \u0111\u1ec1 thi th\u1eed b\u00e1m s\u00e1t ma tr\u1eadn chu\u1ea9n:<\/p>\n<div style=\"background-color: #f7fafc; border: 1px solid #e2e8f0; border-radius: 8px; padding: 20px; margin: 20px 0;\">\n<h3 style=\"color: #2b6cb0; font-size: 17px; margin-top: 0; margin-bottom: 12px;\">C\u1ea5u tr\u00fac chu\u1ea9n b\u1ed9 \u0111\u1ec1 thi m\u1eabu NaviEdu:<\/h3>\n<ul style=\"padding-left: 20px; margin-bottom: 15px;\">\n<li><strong>Ph\u1ea7n I: Tr\u1eafc nghi\u1ec7m kh\u00e1ch quan (30% &#8211; 3.0 \u0111i\u1ec3m):<\/strong> G\u1ed3m 12 c\u00e2u h\u1ecfi tr\u1ea3i \u0111\u1ec1u c\u00e1c ch\u1ee7 \u0111\u1ec1 nh\u1eadn bi\u1ebft v\u00e0 th\u00f4ng hi\u1ec3u (c\u0103n th\u1ee9c, h\u00e0m s\u1ed1, h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh, t\u1ec9 s\u1ed1 l\u01b0\u1ee3ng gi\u00e1c), gi\u00fap h\u1ecdc sinh l\u1ea5y tr\u1ecdn \u0111i\u1ec3m nhanh ch\u00f3ng.<\/li>\n<li><strong>Ph\u1ea7n II: T\u1ef1 lu\u1eadn (70% &#8211; 7.0 \u0111i\u1ec3m):<\/strong>\n<ul>\n<li><em>B\u00e0i 1 (1.5 \u0111i\u1ec3m):<\/em> R\u00fat g\u1ecdn v\u00e0 gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh quy v\u1ec1 b\u1eadc nh\u1ea5t\/h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh.<\/li>\n<li><em>B\u00e0i 2 (2.0 \u0111i\u1ec3m):<\/em> Gi\u1ea3i b\u00e0i to\u00e1n th\u1ef1c t\u1ebf b\u1eb1ng c\u00e1ch l\u1eadp h\u1ec7 ph\u01b0\u01a1ng tr\u00ecnh.<\/li>\n<li><em>B\u00e0i 3 (1.0 \u0111i\u1ec3m):<\/em> H\u00e0m s\u1ed1 b\u1eadc nh\u1ea5t v\u00e0 \u0111\u1ed3 th\u1ecb (t\u00ednh h\u1ec7 s\u1ed1, t\u00ecm t\u1ecda \u0111\u1ed9 giao \u0111i\u1ec3m).<\/li>\n<li><em>B\u00e0i 4 (2.0 \u0111i\u1ec3m):<\/em> B\u00e0i to\u00e1n h\u00ecnh h\u1ecdc t\u1ed5ng h\u1ee3p (h\u1ec7 th\u1ee9c l\u01b0\u1ee3ng, gi\u1ea3i tam gi\u00e1c vu\u00f4ng v\u00e0 \u1ee9ng d\u1ee5ng \u0111o \u0111\u1ea1c th\u1ef1c t\u1ebf).<\/li>\n<li><em>B\u00e0i 5 (0.5 \u0111i\u1ec3m):<\/em> B\u1ea5t \u0111\u1eb3ng th\u1ee9c ho\u1eb7c t\u00ecm gi\u00e1 tr\u1ecb l\u1edbn nh\u1ea5t\/nh\u1ecf nh\u1ea5t (c\u00e2u h\u1ecfi ph\u00e2n lo\u1ea1i \u0111i\u1ec3m 10).<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<div style=\"text-align: center; margin-top: 25px; padding-top: 15px; border-top: 1px dashed #cbd5e0;\">\n<p style=\"margin-bottom: 15px; font-size: 15px; color: #4a5568;\">To\u00e0n b\u1ed9 t\u00e0i li\u1ec7u g\u1ed3m file \u0111\u1ec1 c\u01b0\u01a1ng \u00f4n t\u1eadp t\u1ed5ng h\u1ee3p, 3 \u0111\u1ec1 thi m\u1eabu c\u00f3 b\u1ea3ng \u0111\u00e1p \u00e1n v\u00e0 thang ch\u1ea5m \u0111i\u1ec3m chi ti\u1ebft t\u1eebng b\u01b0\u1edbc:<\/p>\n<p><a style=\"background-color: #d9534f; color: #ffffff; padding: 12px 28px; text-decoration: none; border-radius: 6px; font-weight: bold; font-size: 16px; display: inline-block; box-shadow: 0 2px 4px rgba(0,0,0,0.1);\" href=\"https:\/\/navi.edu.vn\/thu-vien\/danh-muc-tai-lieu\/lop-9\/\">\ud83d\udce5 T\u1ea2I TR\u1eccN B\u1ed8 \u0110\u1ec0 C\u01af\u01a0NG &amp; \u0110\u1ec0 THI M\u1eaaU (PDF MI\u1ec4N PH\u00cd)<\/a><\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"naviedu-content-section\" style=\"font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif; line-height: 1.8; color: #2d3748; font-size: 16px;\">\n<p>K\u1ef3 thi gi\u1eefa h\u1ecdc k\u00ec 1 kh\u00f4ng ch\u1ec9 l\u00e0 m\u1ed9t c\u1ed9t m\u1ed1c ki\u1ec3m tra ki\u1ebfn th\u1ee9c \u0111\u1ecbnh k\u1ef3, m\u00e0 ch\u00ednh l\u00e0 chi\u1ebfc la b\u00e0n \u0111o l\u01b0\u1eddng m\u1ee9c \u0111\u1ed9 s\u1eb5n s\u00e0ng c\u1ee7a h\u1ecdc sinh l\u1edbp 9 tr\u01b0\u1edbc c\u00e1nh c\u1eeda thi v\u00e0o l\u1edbp 10 \u0111\u1ea7y c\u1ea1nh tranh. M\u1ed9t k\u1ebft qu\u1ea3 t\u1ed1t \u1edf giai \u0111o\u1ea1n n\u00e0y s\u1ebd ti\u1ebfp th\u00eam ngu\u1ed3n \u0111\u1ed9ng l\u1ef1c to l\u1edbn, gi\u00fap c\u00e1c em gi\u1ea3i t\u1ecfa \u00e1p l\u1ef1c t\u00e2m l\u00fd v\u00e0 v\u1eefng v\u00e0ng b\u1ee9t ph\u00e1 trong ch\u1eb7ng \u0111\u01b0\u1eddng \u00f4n luy\u1ec7n ph\u00eda tr\u01b0\u1edbc. <span style=\"font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;\">H\u00e3y b\u1eaft \u0111\u1ea7u ngay h\u00f4m nay t\u1eeb nh\u1eefng b\u01b0\u1edbc \u0111i b\u00e0i b\u1ea3n nh\u1ea5t!<\/span><!-- KH\u1ed0I CTA WORDPRESS CHU\u1ea8N CHUY\u1ec2N \u0110\u1ed4I --><\/p>\n<div style=\"border: 2px dashed #0056b3; background-color: #f4f8ff; border-radius: 10px; padding: 25px; text-align: center; margin: 35px 0;\">\n<h3 style=\"color: #0056b3; margin-top: 0; font-size: 20px; font-weight: bold;\">B\u1ee9t Ph\u00e1 \u0110i\u1ec3m S\u1ed1 Gi\u1eefa K\u1ef3 1 C\u00f9ng L\u1ed9 Tr\u00ecnh C\u00e1 Nh\u00e2n H\u00f3a T\u1ea1i NaviEdu!<\/h3>\n<p style=\"font-size: 16px; line-height: 1.6; color: #333333; margin-bottom: 20px; max-width: 750px; margin-left: auto; margin-right: auto;\">Con \u0111ang lo l\u1eafng tr\u01b0\u1edbc kh\u1ed1i l\u01b0\u1ee3ng ki\u1ebfn th\u1ee9c To\u00e1n 9? H\u00e3y \u0111\u01b0a con \u0111\u1ebfn c\u01a1 s\u1edf <strong>NaviEdu (33 LK6B M\u1ed7 Lao, L\u00e0ng Vi\u1ec7t Ki\u1ec1u Ch\u00e2u \u00c2u, H\u00e0 \u0110\u00f4ng)<\/strong> \u0111\u1ec3 tham gia <strong>L\u00e0m b\u00e0i test \u0111\u1ea7u v\u00e0o mi\u1ec5n ph\u00ed b\u1eb1ng Math AI<\/strong> v\u00e0 nh\u1eadn <strong>t\u01b0 v\u1ea5n l\u1ed9 tr\u00ecnh h\u1ecdc &#8220;may \u0111o&#8221; 3 gi\u00e1o vi\u00ean k\u00e8m 1 h\u1ecdc sinh<\/strong> ngay h\u00f4m nay!<\/p>\n<div style=\"display: flex; justify-content: center; gap: 15px; flex-wrap: wrap;\"><a style=\"background-color: #0056b3; color: #ffffff; padding: 13px 26px; text-decoration: none; border-radius: 6px; font-weight: bold; font-size: 15px; display: inline-block; box-shadow: 0 2px 4px rgba(0,86,179,0.2);\" href=\"https:\/\/navi.edu.vn\/giai-phap\/dang-ky-tu-van?utm_campaign=All.Blog._Organic.Dieuttm_Testtoan9.cta.1310_._.&amp;utm_medium=Dieuttm\" target=\"_blank\" rel=\"noopener\">L\u00c0M B\u00c0I TEST \u0110\u1ea6U V\u00c0O MI\u1ec4N PH\u00cd<\/a><\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>K\u1ef3 thi gi\u1eefa h\u1ecdc k\u1ef3 1 l\u1edbp 9 ch\u00ednh l\u00e0 b\u00e0i ki\u1ec3m tra b\u01b0\u1edbc ngo\u1eb7t quan tr\u1ecdng \u0111\u1ea7u ti\u00ean c\u1ee7a n\u0103m h\u1ecdc cu\u1ed1i c\u1ea5p. K\u1ebft qu\u1ea3 b\u00e0i thi kh\u00f4ng ch\u1ec9 \u1ea3nh h\u01b0\u1edfng tr\u1ef1c ti\u1ebfp \u0111\u1ebfn \u0111i\u1ec3m s\u1ed1 h\u1ecdc b\u1ea1 m\u00e0 c\u00f2n ph\u1ea3n \u00e1nh ch\u00ednh x\u00e1c th\u1ef1c l\u1ef1c hi\u1ec7n t\u1ea1i c\u1ee7a h\u1ecdc sinh, gi\u00fap gia \u0111\u00ecnh&#8230;<\/p>\n","protected":false},"author":2,"featured_media":2825,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[6],"tags":[],"_links":{"self":[{"href":"https:\/\/navi.edu.vn\/blog\/wp-json\/wp\/v2\/posts\/2812"}],"collection":[{"href":"https:\/\/navi.edu.vn\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/navi.edu.vn\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/navi.edu.vn\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/navi.edu.vn\/blog\/wp-json\/wp\/v2\/comments?post=2812"}],"version-history":[{"count":10,"href":"https:\/\/navi.edu.vn\/blog\/wp-json\/wp\/v2\/posts\/2812\/revisions"}],"predecessor-version":[{"id":2826,"href":"https:\/\/navi.edu.vn\/blog\/wp-json\/wp\/v2\/posts\/2812\/revisions\/2826"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/navi.edu.vn\/blog\/wp-json\/wp\/v2\/media\/2825"}],"wp:attachment":[{"href":"https:\/\/navi.edu.vn\/blog\/wp-json\/wp\/v2\/media?parent=2812"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/navi.edu.vn\/blog\/wp-json\/wp\/v2\/categories?post=2812"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/navi.edu.vn\/blog\/wp-json\/wp\/v2\/tags?post=2812"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}