{"article_info":{"article_id":149217,"cat_id":1543,"cat_title":"Vở thực hành Toán 8","publish_time":1693964160,"cat_id2":1543,"is_link":0,"thumbnail":"https://img.loigiaihay.com/picture/article/2023/0906/resize_1-0_9.png","title":"Giải bài 2 trang 21 vở thực hành Toán 8 tập 2","label":"Bài 2 trang 21","alias":"giai-bai-2-trang-21-vo-thuc-hanh-toan-8-tap-2","introtext":"Hãy thực hiện các phép tính đã chỉ ra.","content":"<style>\r\n.method-close-icon{position: relative;float: right;top: 6px;transform: rotate(270deg);-ms-transform:rotate(270deg);-moz-transform:rotate(270deg);-webkit-transform:rotate(270deg);-o-transform:rotate(270deg);}\r\n.method-open-icon{position: relative;float: right;top: 6px;}\r\n</style>\r\n<p><strong style=\"font-size: 16px;\">Đề bài</strong></p><p>Hãy thực hiện các phép tính đã chỉ ra.</p>\r\n<p>a) \\(\\frac{{4{\\rm{x}} - 6}}{{5{{\\rm{x}}^2} - x}}.\\frac{{25{{\\rm{x}}^2} - 10{\\rm{x}} + 1}}{{27 + 8{{\\rm{x}}^3}}}\\);</p>\r\n<p>b) \\(\\frac{{2{\\rm{x}} + 10}}{{{{\\left( {x - 3} \\right)}^2}}}:\\frac{{{{\\left( {x + 5} \\right)}^3}}}{{{x^2} - 9}}\\).</p><div id=\"pos_end_question\"></div><div style=\"padding-top: 10px;padding-bottom: 2px;margin-bottom: 10px;\"><p class=\"show-detail-method\" style=\"background: #654bc2;text-align: center;border-radius:5px;padding: 10px;margin-bottom: 0px;\" onclick=\"showDetailMethod();\"><strong style=\"font-size: 16px;\">Phương pháp giải - Xem chi tiết</strong><img class=\"method-open-icon\" id=\"method_colapse_icon\" src=\"data:image/png;base64,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\"></p>  <div class=\"content_method_content\" style=\"padding: 10px 10px 5px 10px;border: dashed 1px #654bc2;border-top:none;\"><p>- Muốn nhân hai phân thức, ta nhân các tử thức với nhau, các mẫu thức với nhau.</p>\r\n<p><span class=\"MTConvertedEquation\">\\(\\frac{A}{B}.\\frac{C}{D} = \\frac{{A.C}}{{B.D}}\\)</span><em>.</em></p>\r\n<p>- Muốn chia phân thức <span class=\"MTConvertedEquation\">\\(\\frac{A}{B}\\)</span> cho phân thức <span class=\"MTConvertedEquation\">\\(\\frac{C}{D}\\)</span> khác 0, ta nhân phân thức <span class=\"MTConvertedEquation\">\\(\\frac{A}{B}\\)</span> với phân thức <span class=\"MTConvertedEquation\">\\(\\frac{D}{C}\\)</span>:        </p>\r\n<p><span class=\"MTConvertedEquation\">\\(\\frac{A}{B}:\\frac{C}{D} = \\frac{A}{B}.\\frac{D}{C}\\)</span>, với <span class=\"MTConvertedEquation\">\\(\\frac{C}{D} \\ne 0\\)</span>.</p>  </div>\r\n<script type=\"text/javascript\">\r\n    var is_open =true;\r\n    function showDetailMethod(){\r\n        if(is_open){\r\n            document.querySelector(\".content_method_content\").style.display='none';\r\n            document.getElementById(\"method_colapse_icon\").classList.remove(\"method-open-icon\");\r\n            document.getElementById(\"method_colapse_icon\").classList.add(\"method-close-icon\");\r\n        }else{\r\n            document.querySelector(\".content_method_content\").style.display='block';\r\n            document.getElementById(\"method_colapse_icon\").classList.remove(\"method-close-icon\");\r\n            document.getElementById(\"method_colapse_icon\").classList.add(\"method-open-icon\");\r\n        }\r\n        is_open = !is_open;\r\n    }\r\n</script>\r\n</div><p><strong style=\"font-size: 16px;\">Lời giải chi tiết</strong></p><p>a) <span class=\"MTConvertedEquation\">\\(\\frac{{4{\\rm{x}} - 6}}{{5{{\\rm{x}}^2} - x}}.\\frac{{25{{\\rm{x}}^2} - 10{\\rm{x}} + 1}}{{27 + 8{{\\rm{x}}^3}}} = \\frac{{\\left( {4{\\rm{x}} - 6} \\right)\\left( {25{{\\rm{x}}^2} - 10{\\rm{x}} + 1} \\right)}}{{\\left( {5{{\\rm{x}}^2} - x} \\right)\\left( {27 + 8{{\\rm{x}}^3}} \\right)}}\\)</span></p>\r\n<p><span class=\"MTConvertedEquation\">\\( = \\frac{{ - 2\\left( {3 - 2{\\rm{x}}} \\right){{\\left( {5{\\rm{x}} - 1} \\right)}^2}}}{{x\\left( {5{\\rm{x}} - 1} \\right)\\left( {3 - 2{\\rm{x}}} \\right)\\left( {9 + 6{\\rm{x}} + 4{{\\rm{x}}^2}} \\right)}} = \\frac{{ - 2\\left( {5{\\rm{x}} - 1} \\right)}}{{x\\left( {9 + 6{\\rm{x}} + 4{{\\rm{x}}^2}} \\right)}}\\)</span></p>\r\n<p>b) <span class=\"MTConvertedEquation\">\\(\\frac{{2{\\rm{x}} + 10}}{{{{\\left( {x - 3} \\right)}^2}}}:\\frac{{{{\\left( {x + 5} \\right)}^3}}}{{{x^2} - 9}} = \\frac{{2{\\rm{x}} + 10}}{{{{\\left( {x - 3} \\right)}^2}}}.\\frac{{{x^2} - 9}}{{{{\\left( {x + 5} \\right)}^2}}}\\)</span></p>\r\n<p><span class=\"MTConvertedEquation\">\\( = \\frac{{2\\left( {x + 5} \\right)}}{{{{\\left( {x - 3} \\right)}^2}}}.\\frac{{\\left( {x - 3} \\right)\\left( {x + 3} \\right)}}{{{{\\left( {x + 5} \\right)}^3}}} = \\frac{{2\\left( {x + 3} \\right)}}{{\\left( {x - 3} \\right){{\\left( {x + 5} \\right)}^2}}}\\)</span>.</p>","common_article":"","display_type":1,"vungoi_exam_id":"","article_type":1,"cmt_count":0,"zip_status":1,"last_modified_time":1693964327,"last_zip_time":1693964327,"zip_link":"https://offline.loigiaihay.com/articles/1543/149217/149217_1693964327.zip","picture":"https://img.loigiaihay.com/picture/article/2023/0906/1-0_9.png","youtube_id":"","video_start_time":"0","quizlet_id":"0","ref_article_id":0,"readmore_display_type":0,"wiki":0,"comment_url":"https://loigiaihay.com/comment/giai-bai-2-trang-21-vo-thuc-hanh-toan-8-tap-2-c1543a149217.html","origin_url":"https://loigiaihay.com/giai-bai-2-trang-21-vo-thuc-hanh-toan-8-tap-2-c1543a149217.html","relate_link":[],"exam_file":"","solution_file":""},"callouts":[],"relate_articles":[],"others_in_cat":[{"article_id":149218,"cat_id":1543,"publish_time":1693964280,"is_link":0,"thumbnail":"https://img.loigiaihay.com/picture/article/2023/0906/resize_1-0_10.png","title":"Giải bài 3 trang 22 vở thực hành Toán 8 tập 2","alias":"giai-bai-3-trang-22-vo-thuc-hanh-toan-8-tap-2","introtext":"Hãy thực hiện các phép tính đã chỉ ra.","display_type":1,"article_type":1},{"article_id":149219,"cat_id":1543,"publish_time":1693964400,"is_link":0,"thumbnail":"https://img.loigiaihay.com/picture/article/2023/0906/resize_1-0_11.png","title":"Giải bài 4 trang 22 vở thực hành Toán 8 tập 2","alias":"giai-bai-4-trang-22-vo-thuc-hanh-toan-8-tap-2","introtext":"Cho biểu thức \\(P = \\frac{{{x^2} - 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