{"common":{"save":0,"post_id":"4760","level":2,"total":10,"point":10,"point_extra":0},"segment":[{"id":"7823","post_id":"4760","mon_id":"1158113","chapter_id":"1158119","question":"<p>Tìm x bi\u1ebft<\/p><p><span class=\"math-tex\">$\\dfrac{x}{13}=\\dfrac{-3}{39}$<\/span><\/p>","options":["x = 1","x = -1","x = 2","x = -2"],"correct":"2","level":"2","hint":"<p>Áp d\u1ee5ng quy t\u1eafc b\u1eb1ng nhau c\u1ee7a hai phân s\u1ed1 <\/p><p><span class=\"math-tex\">$\\dfrac{a}{b}=\\dfrac{c}{d}$<\/span> n\u1ebfu a . d = b . c<\/p>","answer":"<p>Vì <span class=\"math-tex\">$\\dfrac{x}{13}=\\dfrac{-3}{39}$<\/span> nên x . 39 = 13 . (-3) = -39 suy ra x = (-39) : 39 = -1<\/p><p>V\u1eady x = -1<\/p><p>\u0110áp án \u0111úng là <span style=\"color:#16a085;\"><strong>x = -1<\/strong><\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"1","date":"2021-09-30 03:28:09","option_type":"txt","len":0},{"id":"7825","post_id":"4760","mon_id":"1158113","chapter_id":"1158119","question":"<p>Ch\u1ecdn phép so sánh <strong>\u0111úng<\/strong><\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$\\dfrac{18}{26}=\\dfrac{9}{14}$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$\\dfrac{-25}{30}=\\dfrac{-5}{6}$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$\\dfrac{36}{14}=\\dfrac{18}{5}$<\/span>"],"correct":"2","level":"2","hint":"<p>Áp d\u1ee5ng tính ch\u1ea5t chia c\u1ea3 t\u1eed và m\u1eabu c\u1ee7a m\u1ed9t phân s\u1ed1 v\u1edbi cùng m\u1ed9t \u01b0\u1edbc chung c\u1ee7a chúng \u0111\u1ec3 rút g\u1ecdn phân s\u1ed1 th\u1ee9 nh\u1ea5t r\u1ed3i ki\u1ec3m tra xem nó có b\u1eb1ng phân s\u1ed1 th\u1ee9 hai hay không.<\/p>","answer":"<p><strong>A.<\/strong> <span class=\"math-tex\">$\\dfrac{18}{26}=\\dfrac{9}{14}$<\/span> (<span style=\"color:#c0392b;\">sai <\/span>vì <span class=\"math-tex\">$\\dfrac{18}{26}=\\dfrac{18:2}{26:2}=\\dfrac{9}{13}$<\/span>)<\/p><p><strong>B.<\/strong> <span class=\"math-tex\">$\\dfrac{-25}{30}=\\dfrac{-5}{6}$<\/span> (<span style=\"color:#16a085;\">\u0111úng <\/span>vì <span class=\"math-tex\">$\\dfrac{-25}{30}=\\dfrac{-25:5}{30:5}=\\dfrac{-5}{6}$<\/span> )<\/p><p><strong>C.<\/strong> <span class=\"math-tex\">$\\dfrac{36}{14}=\\dfrac{18}{5}$<\/span> (<span style=\"color:#c0392b;\">sai <\/span>vì <span class=\"math-tex\">$\\dfrac{36}{14}=\\dfrac{36:2}{14:2}=\\dfrac{18}{7}$<\/span> )<\/p><p>\u0110áp án \u0111úng là <span style=\"color:#16a085;\"><strong>B.<\/strong> <span class=\"math-tex\">$\\dfrac{-25}{30}=\\dfrac{-5}{6}$<\/span><\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"3","date":"2021-09-30 03:34:48","option_type":"math","len":0},{"id":"7827","post_id":"4760","mon_id":"1158113","chapter_id":"1158119","question":"<p>Tìm s\u1ed1 nguyên x bi\u1ebft<\/p><p><span class=\"math-tex\">$\\dfrac{8}{x}=\\dfrac{6}{-9}$<\/span><\/p>","options":["x = -12","x = 12"],"correct":"1","level":"2","hint":"<p>Hai phân s\u1ed1 <span class=\"math-tex\">$\\dfrac{a}{b}$<\/span> và <span class=\"math-tex\">$\\dfrac{c}{d}$<\/span> b\u1eb1ng nhau n\u1ebfu a . d = b . c<\/p>","answer":"<p>Vì <span class=\"math-tex\">$\\dfrac{8}{x}=\\dfrac{6}{-9}$<\/span> nên 8 . (-9) = x . 6 hay -72 = 6x. Suy ra x = (-72) : 6 = -12<\/p><p>V\u1eady x = -12<\/p><p>\u0110áp án \u0111úng là <span style=\"color:#16a085;\"><strong> x = -12<\/strong><\/span><\/p>","type":"choose","extra_type":"shape1","time":"0","user_id":"131","test":"1","date":"2021-09-30 03:39:32","option_type":"txt","len":0}]}
