B\u00e0i 1 (trang 25 SGK H\u00ecnh h\u1ecdc 12):\u00a0T\u00ednh th\u1ec3 t\u00edch kh\u1ed1i t\u1ee9 di\u1ec7n \u0111\u1ec1u c\u1ea1nh a<\/strong><\/span><\/p>\nL\u1eddi gi\u1ea3i:<\/b><\/p>\n
![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-1-trang-25-sgk-hinh-hoc-12.png\")
<\/p>\n
![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-1-trang-25-sgk-hinh-hoc-12-12.png\")
<\/p>\n
B\u00e0i 2 (trang 25 SGK H\u00ecnh h\u1ecdc 12):\u00a0T\u00ednh th\u1ec3 t\u00edch kh\u1ed1i b\u00e1t di\u1ec7n \u0111\u1ec1u c\u1ea1nh a.<\/strong><\/span><\/p>\nL\u1eddi gi\u1ea3i:<\/b><\/p>\n
![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-2-trang-25-sgk-hinh-hoc-12.png\")
![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-2-trang-25-sgk-hinh-hoc-12-1.png\")
<\/p>\n
B\u00e0i 3 (trang 25 SGK H\u00ecnh h\u1ecdc 12):\u00a0Cho kh\u1ed1i h\u1ed9p ABCD.A\u2019B\u2019C\u2019D\u2019. T\u00ednh t\u1ec9 s\u1ed1 gi\u1eefa th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i h\u1ed9p \u0111\u00f3 v\u00e0 th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i t\u1ee9 di\u1ec7n ACB\u2019D\u2019.<\/strong><\/span><\/p>\nL\u1eddi gi\u1ea3i:<\/b><\/p>\n
![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-3-trang-25-sgk-hinh-hoc-12.png\")
![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-3-trang-25-sgk-hinh-hoc-12-1.png\")
<\/p>\n
B\u00e0i 4 (trang 25 SGK H\u00ecnh h\u1ecdc 12):\u00a0Cho kh\u1ed1i ch\u00f3p S.ABC. Tr\u00ean c\u00e1c \u0111o\u1ea1n th\u1eb1ng SA, SB, SC l\u1ea7n l\u01b0\u1ee3t l\u1ea5y ba \u0111i\u1ec3m A\u2019, B\u2019, C\u2019 kh\u00e1c v\u1edbi S. Ch\u1ee9ng minh r\u1eb1ng:<\/strong><\/span><\/p>\n![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-4-trang-25-sgk-hinh-hoc-12.png\")
<\/p>\n
L\u1eddi gi\u1ea3i<\/strong><\/p>\n\n
![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-4-trang-25-sgk-hinh-hoc-12-2.png\")
<\/p>\n
G\u1ecdi H v\u00e0 K l\u1ea7n l\u01b0\u1ee3t l\u00e0 h\u00ecnh chi\u1ebfu vu\u00f4ng g\u00f3c c\u1ee7a A v\u00e0 A\u2019 tr\u00ean mp(SBC), \u0111\u1eb7t AH = h1<\/sub>\u00a0v\u00e0 A\u2019K = h2<\/sub>\u00a0, S1<\/sub>v\u00e0 S2<\/sub>\u00a0l\u1ea7n l\u01b0\u1ee3t l\u00e0 di\u1ec7n t\u00edch c\u1ee7a hai tam gi\u00e1c SBC v\u00e0 SB\u2019C\u2019, ta c\u00f3:<\/p>\n![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-4-trang-25-sgk-hinh-hoc-12-1.png\")
<\/p>\n
B\u00e0i 5 (trang 26 SGK H\u00ecnh h\u1ecdc 12):\u00a0Cho tam gi\u00e1c ABC, vu\u00f4ng c\u00e2n \u1edf A v\u00e0 AB = a. Tr\u00ean \u0111\u01b0\u1eddng th\u1eb3ng qua C, vu\u00f4ng g\u00f3c v\u1edbi m\u1eb7t ph\u1eb3ng (ABC) l\u1ea5y \u0111i\u1ec3m D sao cho CD = a. M\u1eb7t ph\u1eb3ng qua C vu\u00f4ng g\u00f3c v\u1edbi BD c\u1eaf BD t\u1ea1i F v\u00e0 c\u1eaft AD t\u1ea1i E. T\u00ednh th\u1ec3 t\u00edch kh\u1ed1i t\u1ee9 di\u1ec7n CDEF theo a.<\/strong><\/span><\/p>\nL\u1eddi gi\u1ea3i:<\/b><\/p>\n
![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-5-trang-26-sgk-hinh-hoc-12.png\")
![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-5-trang-26-sgk-hinh-hoc-12-1.png\")
<\/p>\n
B\u00e0i 6 (trang 26 SGK H\u00ecnh h\u1ecdc 12):\u00a0Cho hai \u0111\u01b0\u1eddng th\u1eb3ng ch\u00e9o nhau d v\u00e0 d\u2019. \u0110o\u1ea1n th\u1eb3ng AB c\u00f3 \u0111\u1ed9 d\u00e0i b\u1eb1ng a tr\u01b0\u1ee3t tr\u00ean d, \u0111o\u1ea1n th\u1eb3ng CD c\u00f3 \u0111\u1ed9 d\u00e0i b\u1eb1ng b tr\u01b0\u1ee3t tr\u00ean d\u2019. Ch\u1ee9ng minh r\u1eb1ng kh\u1ed1i t\u1ee9 di\u1ec7n ABCD c\u00f3 th\u1ec3 t\u00edch kh\u00f4ng \u0111\u1ed5i.<\/strong><\/span><\/p>\nL\u1eddi gi\u1ea3i:<\/b><\/p>\n
![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-6-trang-26-sgk-hinh-hoc-12.png\")
![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-6-trang-26-sgk-hinh-hoc-12-1.png\")
<\/p>\n
<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"
B\u00e0i 1 (trang 25 SGK H\u00ecnh h\u1ecdc 12):\u00a0T\u00ednh th\u1ec3 t\u00edch kh\u1ed1i t\u1ee9 di\u1ec7n \u0111\u1ec1u c\u1ea1nh a L\u1eddi gi\u1ea3i: B\u00e0i 2 (trang 25 SGK H\u00ecnh h\u1ecdc 12):\u00a0T\u00ednh th\u1ec3 t\u00edch kh\u1ed1i b\u00e1t di\u1ec7n \u0111\u1ec1u c\u1ea1nh a. L\u1eddi gi\u1ea3i: B\u00e0i 3 (trang 25 SGK H\u00ecnh h\u1ecdc 12):\u00a0Cho kh\u1ed1i h\u1ed9p ABCD.A\u2019B\u2019C\u2019D\u2019. T\u00ednh t\u1ec9 s\u1ed1 gi\u1eefa th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i […]<\/p>\n","protected":false},"author":3,"featured_media":20706,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_mi_skip_tracking":false,"tdm_status":"","tdm_grid_status":""},"categories":[1298],"tags":[1377,1356,1355],"yoast_head":"\n
H\u00ecnh H\u1ecdc - Ch\u01b0\u01a1ng I - B\u00e0i 3: Kh\u00e1i ni\u1ec7m v\u1ec1 th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i \u0111a di\u1ec7n<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/lop12.edu.vn\/hinh-hoc-chuong-bai-3-khai-niem-ve-tich-cua-khoi-da-dien\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"H\u00ecnh H\u1ecdc - Ch\u01b0\u01a1ng I - B\u00e0i 3: Kh\u00e1i ni\u1ec7m v\u1ec1 th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i \u0111a di\u1ec7n\" \/>\n<meta property=\"og:description\" content=\"B\u00e0i 1 (trang 25 SGK H\u00ecnh h\u1ecdc 12):\u00a0T\u00ednh th\u1ec3 t\u00edch kh\u1ed1i t\u1ee9 di\u1ec7n \u0111\u1ec1u c\u1ea1nh a L\u1eddi gi\u1ea3i: B\u00e0i 2 (trang 25 SGK H\u00ecnh h\u1ecdc 12):\u00a0T\u00ednh th\u1ec3 t\u00edch kh\u1ed1i b\u00e1t di\u1ec7n \u0111\u1ec1u c\u1ea1nh a. 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T\u00ednh t\u1ec9 s\u1ed1 gi\u1eefa th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i […]","og_url":"https:\/\/lop12.edu.vn\/hinh-hoc-chuong-bai-3-khai-niem-ve-tich-cua-khoi-da-dien\/","og_site_name":"Lop12.edu.vn - C\u1ed9ng \u0111\u1ed3ng h\u1ecdc sinh l\u1edbp 12 l\u1edbn nh\u1ea5t t\u1ea1i Vi\u1ec7t Nam","article_published_time":"2018-03-13T04:23:39+00:00","og_image":[{"width":388,"height":389,"url":"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2018\/03\/bai-1-trang-25-sgk-hinh-hoc-12.png","type":"image\/png"}],"author":"H\u00e0 Trang","twitter_card":"summary_large_image","twitter_misc":{"Written by":"H\u00e0 Trang","Est. reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/lop12.edu.vn\/hinh-hoc-chuong-bai-3-khai-niem-ve-tich-cua-khoi-da-dien\/","url":"https:\/\/lop12.edu.vn\/hinh-hoc-chuong-bai-3-khai-niem-ve-tich-cua-khoi-da-dien\/","name":"H\u00ecnh H\u1ecdc - Ch\u01b0\u01a1ng I - B\u00e0i 3: Kh\u00e1i ni\u1ec7m v\u1ec1 th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i \u0111a di\u1ec7n","isPartOf":{"@id":"https:\/\/lop12.edu.vn\/#website"},"datePublished":"2018-03-13T04:23:39+00:00","dateModified":"2018-03-13T04:23:39+00:00","author":{"@id":"https:\/\/lop12.edu.vn\/#\/schema\/person\/2da855e5d06b553ac0065157cc261a45"},"breadcrumb":{"@id":"https:\/\/lop12.edu.vn\/hinh-hoc-chuong-bai-3-khai-niem-ve-tich-cua-khoi-da-dien\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/lop12.edu.vn\/hinh-hoc-chuong-bai-3-khai-niem-ve-tich-cua-khoi-da-dien\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/lop12.edu.vn\/hinh-hoc-chuong-bai-3-khai-niem-ve-tich-cua-khoi-da-dien\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/lop12.edu.vn\/"},{"@type":"ListItem","position":2,"name":"H\u00ecnh H\u1ecdc – Ch\u01b0\u01a1ng I – B\u00e0i 3: Kh\u00e1i ni\u1ec7m v\u1ec1 th\u1ec3 t\u00edch c\u1ee7a kh\u1ed1i \u0111a di\u1ec7n"}]},{"@type":"WebSite","@id":"https:\/\/lop12.edu.vn\/#website","url":"https:\/\/lop12.edu.vn\/","name":"Lop12.edu.vn - C\u1ed9ng \u0111\u1ed3ng h\u1ecdc sinh l\u1edbp 12","description":"","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/lop12.edu.vn\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-US"},{"@type":"Person","@id":"https:\/\/lop12.edu.vn\/#\/schema\/person\/2da855e5d06b553ac0065157cc261a45","name":"H\u00e0 Trang","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/lop12.edu.vn\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/545a8100db1147f314111301d261dc33?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/545a8100db1147f314111301d261dc33?s=96&d=mm&r=g","caption":"H\u00e0 Trang"},"url":"https:\/\/lop12.edu.vn\/author\/trangvth2\/"}]}},"_links":{"self":[{"href":"https:\/\/lop12.edu.vn\/wp-json\/wp\/v2\/posts\/20705"}],"collection":[{"href":"https:\/\/lop12.edu.vn\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lop12.edu.vn\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lop12.edu.vn\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/lop12.edu.vn\/wp-json\/wp\/v2\/comments?post=20705"}],"version-history":[{"count":2,"href":"https:\/\/lop12.edu.vn\/wp-json\/wp\/v2\/posts\/20705\/revisions"}],"predecessor-version":[{"id":20731,"href":"https:\/\/lop12.edu.vn\/wp-json\/wp\/v2\/posts\/20705\/revisions\/20731"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/lop12.edu.vn\/wp-json\/wp\/v2\/media\/20706"}],"wp:attachment":[{"href":"https:\/\/lop12.edu.vn\/wp-json\/wp\/v2\/media?parent=20705"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lop12.edu.vn\/wp-json\/wp\/v2\/categories?post=20705"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lop12.edu.vn\/wp-json\/wp\/v2\/tags?post=20705"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}