{"segment":[{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"Mu\u1ed1n nh\u00e2n 2 ph\u00e2n s\u1ed1 ta l\u00e0m nh\u01b0 sau:","select":["A. Ta nh\u00e2n t\u1eed s\u1ed1 v\u1edbi t\u1eed s\u1ed1 v\u00e0 gi\u1eef nguy\u00ean m\u1eabu s\u1ed1 ","B. Ta nh\u00e2n t\u1eed s\u1ed1 v\u1edbi t\u1eed s\u1ed1 v\u00e0 nh\u00e2n m\u1eabu s\u1ed1 v\u1edbi m\u1eabu s\u1ed1 "],"hint":"","explain":"<span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> Theo quy t\u1eafc nh\u00e2n hai ph\u00e2n s\u1ed1: Mu\u1ed1n nh\u00e2n hai ph\u00e2n s\u1ed1 ta nh\u00e2n t\u1eed s\u1ed1 v\u1edbi t\u1eed s\u1ed1 v\u00e0 nh\u00e2n m\u1eabu s\u1ed1 v\u1edbi m\u1eabu s\u1ed1 <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B <\/span> ","column":1}]}],"id_ques":1651},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang th\u1ec3 hi\u1ec7n t\u00ednh ch\u1ea5t k\u1ebft h\u1ee3p c\u1ee7a ph\u00e9p nh\u00e2n ph\u00e2n s\u1ed1: <br\/> $\\left( \\dfrac{a}{b} . \\dfrac{c}{d} \\right) . \\dfrac{m}{n}$ = ? ","select":["A. $\\dfrac{a . m}{b . n} . \\dfrac{c . m}{d . n} $ ","B. $ \\dfrac{a}{b} . \\left( \\dfrac{c}{d} . \\dfrac{m}{n} \\right) $ ","C. $ \\dfrac{a . c}{b . d} . \\dfrac{m}{n} $ "],"hint":"","explain":"<span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> Theo t\u00ednh ch\u1ea5t k\u1ebft h\u1ee3p c\u1ee7a ph\u00e9p nh\u00e2n ta c\u00f3: <br\/> $\\left( \\dfrac{a}{b} . \\dfrac{c}{d} \\right) . \\dfrac{m}{n} = \\dfrac{a}{b} . \\left( \\dfrac{c}{d} . \\dfrac{m}{n} \\right) $ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B <\/span> ","column":3}]}],"id_ques":1652},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c $\\dfrac{-4}{5} . \\dfrac{3}{2} . \\dfrac{-10}{11}$ l\u00e0: ","select":["A. $\\dfrac{-12}{11} $ ","B. $ \\dfrac{12}{11}$ ","C. $ \\dfrac{-30}{55} $ ","D. $ \\dfrac{60}{22}$"],"hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> Mu\u1ed1n nh\u00e2n hai ph\u00e2n s\u1ed1 ta nh\u00e2n t\u1eed s\u1ed1 v\u1edbi t\u1eed s\u1ed1 v\u00e0 nh\u00e2n m\u1eabu s\u1ed1 v\u1edbi m\u1eabu s\u1ed1 <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> $\\dfrac{-4}{5} . \\dfrac{3}{2} . \\dfrac{-10}{11} = \\dfrac{-4 . 3 . (-10)}{5 . 2 . 11} = \\dfrac{120}{110} = \\dfrac{12}{11}$ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B. $\\dfrac{12}{11}$ <\/span> <br\/> <span class='basic_green'> <i> Nh\u1eadn x\u00e9t: N\u00ean r\u00fat g\u1ecdn c\u00e1c ph\u00e2n s\u1ed1 \u0111\u1ebfn t\u1ed1i gi\u1ea3n tr\u01b0\u1edbc v\u00e0 sau khi th\u1ef1c hi\u1ec7n ph\u00e9p t\u00ednh <\/i><\/span> ","column":4}]}],"id_ques":1653},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c $\\dfrac{-8}{9} . \\dfrac{15}{-16} . \\dfrac{-21}{20}$ l\u00e0: ","select":["A. $\\dfrac{-7}{8} $ ","B. $ \\dfrac{7}{8}$ ","C. $ \\dfrac{2521}{2880} $ ","D. $ \\dfrac{315}{-180}$"],"hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> Mu\u1ed1n nh\u00e2n hai ph\u00e2n s\u1ed1 ta nh\u00e2n t\u1eed s\u1ed1 v\u1edbi t\u1eed s\u1ed1 v\u00e0 nh\u00e2n m\u1eabu s\u1ed1 v\u1edbi m\u1eabu s\u1ed1 <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> $\\dfrac{-8}{9} . \\dfrac{15}{-16} . \\dfrac{-21}{20} = \\dfrac{-8 . 15 . (-21)}{9 . (-16) . 20} = \\dfrac{2520}{-2880} = \\dfrac{-7}{8}$ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: A. $\\dfrac{-7}{8}$ <\/span> ","column":4}]}],"id_ques":1654},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c $\\dfrac{-4}{7} : (-2) - \\dfrac{1}{4} . (-6)$ l\u00e0: ","select":["A. $\\dfrac{25}{14} $ ","B. $ \\dfrac{-17}{14}$ ","C. $ \\dfrac{-25}{14} $ ","D. $ \\dfrac{3}{14}$"],"hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b> T\u00ednh $\\dfrac{-4}{7} : (-2)$ b\u1eb1ng c\u00e1ch l\u1ea5y $\\dfrac{-4}{7}$ nh\u00e2n v\u1edbi ngh\u1ecbch \u0111\u1ea3o c\u1ee7a (-2) <br\/> <b> B\u01b0\u1edbc 2: <\/b> T\u00ednh $\\dfrac{1}{4} . (-6)$ b\u1eb1ng c\u00e1ch nh\u00e2n t\u1eed s\u1ed1 v\u1edbi (-6) v\u00e0 gi\u1eef nguy\u00ean m\u1eabu s\u1ed1 <br\/> <b> B\u01b0\u1edbc 3: <\/b> Quy \u0111\u1ed3ng v\u00e0 th\u1ef1c hi\u1ec7n tr\u1eeb hai ph\u00e2n s\u1ed1 <\/span> <br\/><br\/> <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> $\\begin{align*} \\dfrac{-4}{7} : (-2) - \\dfrac{1}{4} . (-6) &= \\dfrac{-4}{7} . \\dfrac{-1}{2} - \\dfrac{1 . (-6)}{4} \\\\ &= \\dfrac{-4 . (-1)}{7 . 2} - \\dfrac{-3}{2} \\\\ &= \\dfrac{4}{14} - \\dfrac{-21}{14} \\\\ &= \\dfrac{4 - (-21)}{14} \\\\ &= \\dfrac{25}{14} \\end{align*} $ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: A. $\\dfrac{25}{14}$ <\/span> ","column":4}]}],"id_ques":1655},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c $\\dfrac{3}{-11} : \\dfrac{4}{-7} : \\dfrac{1}{5}$ l\u00e0: ","select":["A. $\\dfrac{12}{385} $ ","B. $ \\dfrac{-105}{44}$ ","C. $ \\dfrac{105}{44} $ ","D. M\u1ed9t \u0111\u00e1p \u00e1n kh\u00e1c "],"hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> Mu\u1ed1n chia hai ph\u00e2n s\u1ed1 ta l\u1ea5y ph\u00e2n s\u1ed1 th\u1ee9 nh\u1ea5t nh\u00e2n v\u1edbi ngh\u1ecbch \u0111\u1ea3o c\u1ee7a ph\u00e2n s\u1ed1 th\u1ee9 hai <\/span> <br\/><br\/> <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> $\\dfrac{3}{-11} : \\dfrac{4}{-7} : \\dfrac{1}{5} = \\dfrac{3}{-11} . \\dfrac{-7}{4} . \\dfrac{5}{1} = \\dfrac{3 . (-7) . 5}{-11 . 4 . 1} = \\dfrac{-105}{-44} = \\dfrac{105}{44} $ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: C. $\\dfrac{105}{44}$ <\/span> ","column":4}]}],"id_ques":1656},{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["-5"],["4"]]],"list":[{"point":5,"width":50,"type_input":"","input_hint":["frac"],"ques":" Ngh\u1ecbch \u0111\u1ea3o c\u1ee7a ph\u00e2n s\u1ed1 $\\dfrac{-4}{5}$ l\u00e0: <div class=\"frac123\"><div class=\"ts\">_input_<\/div><div class=\"ms\">_input_<\/div><\/div>","hint":"Hai s\u1ed1 g\u1ecdi l\u00e0 ngh\u1ecbch \u0111\u1ea3o n\u1ebfu t\u00edch c\u1ee7a ch\u00fang b\u1eb1ng 1","explain":" <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> Ta c\u00f3: $\\dfrac{-4}{5} . \\dfrac{-5}{4} = \\dfrac{(-4).(-5)}{4 . 5} = 1$ <br\/> N\u00ean $\\dfrac{-5}{4}$ l\u00e0 ngh\u1ecbch \u0111\u1ea3o c\u1ee7a ph\u00e2n s\u1ed1 $\\dfrac{-4}{5}$<br\/> <span class='basic_green'> <i> Nh\u1eadn x\u00e9t: Ngh\u1ecbch \u0111\u1ea3o c\u1ee7a ph\u00e2n s\u1ed1 $\\dfrac{a}{b}$ l\u00e0 ph\u00e2n s\u1ed1 $\\dfrac{b}{a}$ <\/i><\/span> "}]}],"id_ques":1657},{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["3"],["2"]]],"list":[{"point":5,"width":50,"ques":" Ngh\u1ecbch \u0111\u1ea3o c\u1ee7a ph\u00e2n s\u1ed1 $\\dfrac{-2}{-3}$ l\u00e0: <div class=\"frac123\"><div class=\"ts\">_input_<\/div><div class=\"ms\">_input_<\/div><\/div>","hint":"Hai s\u1ed1 g\u1ecdi l\u00e0 ngh\u1ecbch \u0111\u1ea3o n\u1ebfu t\u00edch c\u1ee7a ch\u00fang b\u1eb1ng 1","explain":" <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> X\u00e9t ph\u00e2n s\u1ed1 $\\dfrac{-3}{-2}$ <br\/> Ta c\u00f3: $\\dfrac{-3}{-2} . \\dfrac{-2}{-3} = \\dfrac{-3 . (-2)}{-2 . (-3)} = 1$ <br\/> N\u00ean $\\dfrac{-3}{-2} = \\dfrac{3}{2}$ l\u00e0 ngh\u1ecbch \u0111\u1ea3o c\u1ee7a ph\u00e2n s\u1ed1 $\\dfrac{-2}{-3}$ <br\/>"}]}],"id_ques":1658},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"Gi\u00e1 tr\u1ecb x th\u1ecfa m\u00e3n \u0111\u1eb3ng th\u1ee9c $\\dfrac{1}{2} . x - \\dfrac{1}{3} = \\dfrac{-1}{4}$ l\u00e0: ","select":["A. $\\dfrac{1}{6} $ ","B. $ \\dfrac{1}{12}$ ","C. $ \\dfrac{1}{24} $ ","D. $\\dfrac{-1}{6}$ "],"hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b> Coi $\\dfrac{1}{2} . x$ l\u00e0 s\u1ed1 b\u1ecb tr\u1eeb ch\u01b0a bi\u1ebft <br\/> Mu\u1ed1n t\u00ecm s\u1ed1 b\u1ecb tr\u1eeb ch\u01b0a bi\u1ebft ta l\u1ea5y hi\u1ec7u c\u1ed9ng s\u1ed1 tr\u1eeb <br\/> <b> B\u01b0\u1edbc 2: <\/b> Coi x l\u00e0 th\u1eeba s\u1ed1 ch\u01b0a bi\u1ebft <br\/> Mu\u1ed1n t\u00ecm th\u1eeba s\u1ed1 ch\u01b0a bi\u1ebft ta l\u1ea5y t\u00edch chia cho th\u1eeba s\u1ed1 \u0111\u00e3 bi\u1ebft <\/span> <br\/><br\/> <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> $\\begin{align*} \\dfrac{1}{2} . x - \\dfrac{1}{3} &= \\dfrac{-1}{4} \\\\ \\dfrac{1}{2} . x &= \\dfrac{-1}{4} + \\dfrac{1}{3} \\\\ \\dfrac{1}{2} . x &= \\dfrac{-3}{12} + \\dfrac{4}{12} \\\\ \\dfrac{1}{2} . x &= \\dfrac{1}{12} \\\\ x &= \\dfrac{1}{12} : \\dfrac{1}{2} \\\\ x &= \\dfrac{1}{6} \\end{align*} $ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: A. $\\dfrac{1}{6}$ <\/span> ","column":4}]}],"id_ques":1659},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"Gi\u00e1 tr\u1ecb x th\u1ecfa m\u00e3n \u0111\u1eb3ng th\u1ee9c $\\dfrac{2}{5} . x - 2 = \\dfrac{-3}{4}$ l\u00e0: ","select":["A. $\\dfrac{1}{2} $ ","B. $ \\dfrac{25}{8}$ ","C. $ \\dfrac{-1}{2} $ ","D. $\\dfrac{-25}{8}$ "],"hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b> Coi $\\dfrac{2}{5} . x$ l\u00e0 s\u1ed1 b\u1ecb tr\u1eeb ch\u01b0a bi\u1ebft <br\/> Mu\u1ed1n t\u00ecm s\u1ed1 b\u1ecb tr\u1eeb ch\u01b0a bi\u1ebft ta l\u1ea5y hi\u1ec7u c\u1ed9ng s\u1ed1 tr\u1eeb <br\/> <b> B\u01b0\u1edbc 2: <\/b> Coi x l\u00e0 th\u1eeba s\u1ed1 ch\u01b0a bi\u1ebft <br\/> Mu\u1ed1n t\u00ecm th\u1eeba s\u1ed1 ch\u01b0a bi\u1ebft ta l\u1ea5y t\u00edch chia cho th\u1eeba s\u1ed1 \u0111\u00e3 bi\u1ebft <\/span> <br\/><br\/> <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> $\\begin{align*} \\dfrac{2}{5} . x - 2 &= \\dfrac{-3}{4} \\\\ \\dfrac{2}{5} . x &= \\dfrac{-3}{4} + 2 \\\\ \\dfrac{2}{5} . x &= \\dfrac{-3}{4} + \\dfrac{8}{4} \\\\ \\dfrac{2}{5} . x &= \\dfrac{5}{4} \\\\ x &= \\dfrac{5}{4} : \\dfrac{2}{5} \\\\ x &= \\dfrac{25}{8} \\end{align*} $ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B. $\\dfrac{25}{8}$ <\/span> ","column":4}]}],"id_ques":1660},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"Gi\u00e1 tr\u1ecb x th\u1ecfa m\u00e3n \u0111\u1eb3ng th\u1ee9c $-x : \\dfrac{3}{5} + \\dfrac{1}{5} = -4$ l\u00e0: ","select":["A. $\\dfrac{63}{25} $ ","B. $ \\dfrac{-57}{25}$ ","C. $ \\dfrac{-19}{5} $ ","D. $\\dfrac{-19}{3}$ "],"hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b> Coi $x : \\dfrac{3}{5}$ l\u00e0 s\u1ed1 h\u1ea1ng ch\u01b0a bi\u1ebft <br\/> Mu\u1ed1n t\u00ecm s\u1ed1 h\u1ea1ng ch\u01b0a bi\u1ebft ta l\u1ea5y t\u1ed5ng tr\u1eeb \u0111i s\u1ed1 h\u1ea1ng \u0111\u00e3 bi\u1ebft <br\/> <b> B\u01b0\u1edbc 2: <\/b> Coi x l\u00e0 s\u1ed1 b\u1ecb chia ch\u01b0a bi\u1ebft <br\/> Mu\u1ed1n t\u00ecm s\u1ed1 b\u1ecb chia l\u1ea5y th\u01b0\u01a1ng nh\u00e2n v\u1edbi s\u1ed1 chia <\/span> <br\/><br\/> <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> $\\begin{align*} -x : \\dfrac{3}{5} + \\dfrac{1}{5} &= -4 \\\\ -x : \\dfrac{3}{5} &= -4 - \\dfrac{1}{5} \\\\ -x : \\dfrac{3}{5} &= \\dfrac{-20}{5} - \\dfrac{1}{5} \\\\ -x : \\dfrac{3}{5} &= \\dfrac{-21}{5} \\\\ -x &= \\dfrac{-21}{5} . \\dfrac{3}{5} \\\\ -x &= \\dfrac{-21 . 3}{5 . 5} \\\\ -x &= \\dfrac{-63}{25} \\\\ x &= \\dfrac{63}{25} \\end{align*} $ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: A. $\\dfrac{63}{25}$ <\/span> ","column":4}]}],"id_ques":1661},{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["<"]]],"list":[{"point":5,"width":50,"type_input":"","ques":" H\u00e3y \u0111i\u1ec1n d\u1ea5u th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng. <br\/> $\\dfrac{-2}{5} . \\dfrac{4}{-7}$ _input_ $\\dfrac{3}{4} : \\dfrac{2}{3}$ ","hint":"T\u00ednh k\u1ebft qu\u1ea3 hai v\u1ebf, l\u1ef1a ch\u1ecdn ph\u01b0\u01a1ng ph\u00e1p ph\u00f9 h\u1ee3p \u0111\u1ec3 so s\u00e1nh k\u1ebft qu\u1ea3 hai v\u1ebf","explain":" <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> Ta c\u00f3: <br\/> $\\dfrac{-2}{5} . \\dfrac{4}{-7} = \\dfrac{-2 . 4}{5 . (-7)} = \\dfrac{8}{35}$ <br\/> $\\dfrac{3}{4} : \\dfrac{2}{3} = \\dfrac{3}{4} . \\dfrac{3}{2} = \\dfrac{3 . 3 }{4 . 2} = \\dfrac{9}{8}$ <br\/> V\u00ec $\\dfrac{8}{35} < 1$; $\\dfrac{9}{8} > 1$ $\\Rightarrow$ $\\dfrac{8}{35} < \\dfrac{9}{8}$ <br\/> Hay: $\\dfrac{-2}{5} . \\dfrac{4}{-7} < \\dfrac{3}{4} : \\dfrac{2}{3}$<br\/> <span class='basic_pink'>V\u1eady d\u1ea5u c\u1ea7n \u0111i\u1ec1n l\u00e0: < <\/span> "}]}],"id_ques":1662},{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[[">"]]],"list":[{"point":5,"width":50,"type_input":"","ques":" H\u00e3y \u0111i\u1ec1n d\u1ea5u th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng. <br\/> $\\dfrac{3}{8} : \\dfrac{1}{12}$ _input_ $\\dfrac{1}{7} . \\dfrac{-2}{-11}$ ","hint":"T\u00ednh k\u1ebft qu\u1ea3 hai v\u1ebf, l\u1ef1a ch\u1ecdn ph\u01b0\u01a1ng ph\u00e1p ph\u00f9 h\u1ee3p \u0111\u1ec3 so s\u00e1nh k\u1ebft qu\u1ea3 hai v\u1ebf","explain":" <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> Ta c\u00f3: <br\/> $\\dfrac{3}{8} : \\dfrac{1}{12} = \\dfrac{3}{8} . \\dfrac{12}{1} = \\dfrac{3 . 12}{8 . 1}= \\dfrac{9}{2}$ <br\/> $\\dfrac{1}{7} . \\dfrac{-2}{-11} = \\dfrac{1 . (-2)}{7 . (-11)} = \\dfrac{-2}{-77} = \\dfrac{2}{77}$ <br\/> V\u00ec $\\dfrac{9}{2} > 1$; $\\dfrac{2}{77} < 1$ $\\Rightarrow$ $\\dfrac{9}{2} > \\dfrac{2}{77}$ <br\/> Hay: $\\dfrac{3}{8} : \\dfrac{1}{12} > \\dfrac{1}{7} . \\dfrac{-2}{-11}$<br\/> <span class='basic_pink'>V\u1eady d\u1ea5u c\u1ea7n \u0111i\u1ec1n l\u00e0: > <\/span> "}]}],"id_ques":1663},{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["<"]]],"list":[{"point":5,"width":50,"type_input":"","ques":" H\u00e3y \u0111i\u1ec1n d\u1ea5u th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng. <br\/> $\\dfrac{-4}{21} . \\dfrac{-7}{12}$ _input_ $\\dfrac{3}{18} : \\dfrac{2}{9}$ ","hint":"T\u00ednh k\u1ebft qu\u1ea3 hai v\u1ebf, l\u1ef1a ch\u1ecdn ph\u01b0\u01a1ng ph\u00e1p ph\u00f9 h\u1ee3p \u0111\u1ec3 so s\u00e1nh k\u1ebft qu\u1ea3 hai v\u1ebf","explain":" <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> Ta c\u00f3: <br\/> $\\dfrac{-4}{21} . \\dfrac{-7}{12} = \\dfrac{-4 . (-7)}{21 . 12}= \\dfrac{28}{252} = \\dfrac{1}{9}$ <br\/> $\\dfrac{3}{18} : \\dfrac{2}{9} = \\dfrac{1}{6} . \\dfrac{9}{2} = \\dfrac{1 . 9}{6 . 2} = \\dfrac{3}{4}$ <br\/> $\\dfrac{1}{9} = \\dfrac{2}{18} < \\dfrac{9}{18} = \\dfrac{1}{2}$ (1) <br\/> $\\dfrac{3}{4} > \\dfrac{2}{4} = \\dfrac{1}{2}$ (2) <br\/> T\u1eeb (1) v\u00e0 (2) $\\Rightarrow$ $\\dfrac{1}{9} < \\dfrac{3}{4}$ hay: $\\dfrac{-4}{21} . \\dfrac{-7}{12} < \\dfrac{3}{18} : \\dfrac{2}{9}$<br\/> <span class='basic_pink'>V\u1eady d\u1ea5u c\u1ea7n \u0111i\u1ec1n l\u00e0: < <\/span> "}]}],"id_ques":1664},{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["28"],["29"]]],"list":[{"point":5,"width":50,"ques":" T\u00ednh nhanh. <br\/><br\/> $\\dfrac{8}{3} . \\dfrac{2}{5} . \\dfrac{3}{8} . \\dfrac{7}{29} . 10$ = <div class=\"frac123\"><div class=\"ts\">_input_<\/div><div class=\"ms\">_input_<\/div><\/div>","hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> Nh\u00f3m c\u00e1c ph\u00e2n s\u1ed1 m\u00e0 khi nh\u00e2n v\u1edbi nhau c\u00f3 t\u1eed s\u1ed1 v\u00e0 m\u1eabu c\u00f3 th\u1ec3 r\u00fat g\u1ecdn cho nhau \u0111\u01b0\u1ee3c <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> $\\dfrac{8}{3} . \\dfrac{2}{5} . \\dfrac{3}{8} . \\dfrac{7}{29} . 10 \\\\ = \\left( \\dfrac{8}{3} . \\dfrac{3}{8} \\right) . \\left( \\dfrac{2}{5} . 10 \\right) . \\dfrac{7}{29} \\\\ = \\dfrac{8 . 3}{3 . 8} . \\dfrac{2 . 10}{5} . \\dfrac{7}{29} \\\\ = 1 . 4 . \\dfrac{7}{29} \\\\ = \\dfrac{1 . 4 . 7}{29} \\\\ = \\dfrac{28}{29}$ "}]}],"id_ques":1665},{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["12"]]],"list":[{"point":5,"width":50,"type_input":"","input_hint":["frac"],"ques":" T\u00ednh nhanh. <br\/><br\/> $\\dfrac{-9}{43} . \\dfrac{4}{-5} . \\dfrac{43}{9} . 15$ = _input_ ","hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> Nh\u00f3m c\u00e1c ph\u00e2n s\u1ed1 m\u00e0 khi nh\u00e2n v\u1edbi nhau c\u00f3 t\u1eed s\u1ed1 v\u00e0 m\u1eabu c\u00f3 th\u1ec3 r\u00fat g\u1ecdn cho nhau \u0111\u01b0\u1ee3c <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> $\\dfrac{-9}{43} . \\dfrac{4}{-5} . \\dfrac{43}{9} . 15 \\\\ = \\left( \\dfrac{-9}{43} . \\dfrac{43}{9} \\right) . \\left( \\dfrac{4}{-5} . 15 \\right) \\\\ = \\dfrac{-9 . 43}{43 . 9} . \\dfrac{4 . 15}{-5} \\\\ = -1 . (-12) \\\\ = 12$ "}]}],"id_ques":1666},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":" M\u1ed9t \u00f4 t\u00f4 ch\u1ea1y t\u1eeb A \u0111\u1ebfn B v\u1edbi v\u1eadn t\u1ed1c 50km\/h th\u00ec h\u1ebft $\\dfrac{3}{5}$ gi\u1edd. L\u00fac t\u1eeb B \u0111\u1ebfn A xe ch\u1ea1y h\u1ebft $\\dfrac{3}{4}$ gi\u1edd. T\u00ednh v\u1eadn t\u1ed1c l\u00fac v\u1ec1? <br\/> \u0110\u00e1p \u00e1n l\u00e0:","select":["A. 30km\/h ","B. 40km\/h ","C. 50km\/h","D. 45km\/h"],"hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b> T\u00ednh \u0111\u1ed9 d\u00e0i qu\u00e3ng \u0111\u01b0\u1eddng AB: <br\/> Qu\u00e3ng \u0111\u01b0\u1eddng = V\u1eadn t\u1ed1c . Th\u1eddi gian <br\/> <b> B\u01b0\u1edbc 2: <\/b> T\u00ednh v\u1eadn t\u1ed1c l\u00fac v\u1ec1. <br\/> V\u1eadn t\u1ed1c = Qu\u00e3ng \u0111\u01b0\u1eddng : Th\u1eddi gian <\/span> <br\/><br\/> <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> \u0110\u1ed9 d\u00e0i qu\u00e3ng \u0111\u01b0\u1eddng AB l\u00e0: <br\/> $50 . \\dfrac{3}{5} = 30$ (km) <br\/> V\u1eadn t\u1ed1c l\u00fac \u00f4 t\u00f4 \u0111i v\u1ec1 l\u00e0: <br\/> $30 : \\dfrac{3}{4} = 40$ (km\/h) <br\/> \u0110\u00e1p s\u1ed1: 40km\/h <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B. 40km\/h <\/span> ","column":4}]}],"id_ques":1667},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":" Hai v\u00f2i n\u01b0\u1edbc c\u00f9ng ch\u1ea3y v\u00e0o b\u1ec3. V\u00f2i I ch\u1ea3y 1 ph\u00fat \u0111\u01b0\u1ee3c $\\dfrac{1}{30}$ b\u1ec3. V\u00f2i II ch\u1ea3y 1 ph\u00fat \u0111\u01b0\u1ee3c $\\dfrac{1}{45}$ b\u1ec3. H\u1ecfi c\u1ea3 hai v\u00f2i c\u00f9ng ch\u1ea3y sau bao l\u00e2u \u0111\u1ea7y b\u1ec3. <br\/> \u0110\u00e1p \u00e1n l\u00e0:","select":["A. 18 ph\u00fat ","B. 30 ph\u00fat ","C. 45 ph\u00fat","D. 19 ph\u00fat"],"hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b> T\u00ednh trong 1 ph\u00fat c\u1ea3 hai v\u00f2i c\u00f9ng ch\u1ea3y \u0111\u01b0\u1ee3c bao nhi\u00eau ph\u1ea7n b\u1ec3 <br\/> <b> B\u01b0\u1edbc 2: <\/b> T\u00ednh th\u1eddi gian c\u1ea3 hai v\u00f2i c\u00f9ng ch\u1ea3y m\u1ea5t bao l\u00e2u th\u00ec \u0111\u1ea7y b\u1ec3 <\/span> <br\/><br\/> <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> Trong 1 ph\u00fat c\u1ea3 hai v\u00f2i ch\u1ea3y \u0111\u01b0\u1ee3c l\u00e0: <br\/> $\\dfrac{1}{30} + \\dfrac{1}{45} = \\dfrac{1}{18}$ (b\u1ec3) <br\/> Th\u1eddi gian c\u1ea3 hai v\u00f2i ch\u1ea3y \u0111\u1ea7y b\u1ec3 l\u00e0: <br\/> $1 : \\dfrac{1}{18} = 18$ (ph\u00fat) <br\/> \u0110\u00e1p s\u1ed1: 18 ph\u00fat <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: A. 18 ph\u00fat <\/span> ","column":4}]}],"id_ques":1668},{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["83"],["80"]]],"list":[{"point":5,"width":50,"ques":" \u00c1p d\u1ee5ng t\u00ednh ch\u1ea5t ph\u00e2n ph\u1ed1i c\u1ee7a ph\u00e9p nh\u00e2n \u0111\u1ed1i v\u1edbi ph\u00e9p c\u1ed9ng, h\u00e3y t\u00ednh gi\u00e1 tr\u1ecb bi\u1ec3u th\u1ee9c sau: <br\/><br\/> $\\left( \\dfrac{7}{10} + \\dfrac{11}{8} \\right) . \\dfrac{4}{8}$ = <div class=\"frac123\"><div class=\"ts\">_input_<\/div><div class=\"ms\">_input_<\/div><\/div> ","hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> R\u00fat g\u1ecdn c\u00e1c ph\u00e2n s\u1ed1 ch\u01b0a t\u1ed1i gi\u1ea3n <br\/> \u00c1p d\u1ee5ng t\u00ednh ch\u1ea5t ph\u00e2n ph\u1ed1i c\u1ee7a ph\u00e9p nh\u00e2n \u0111\u1ed1i v\u1edbi ph\u00e9p c\u1ed9ng \u0111\u1ec3 nh\u00e2n ph\u00e1 ngo\u1eb7c nh\u01b0 sau: <br\/> $\\left(\\dfrac{a}{b} + \\dfrac{c}{d} \\right) . \\dfrac{e}{f} = \\dfrac{a}{b} . \\dfrac{e}{f} + \\dfrac{c}{d} . \\dfrac{e}{f}$ <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> Ta c\u00f3: <br\/>$ \\begin{align*} \\left( \\dfrac{7}{10} + \\dfrac{11}{8} \\right) . \\dfrac{4}{8} &= \\left( \\dfrac{7}{10} + \\dfrac{11}{8} \\right) . \\dfrac{1}{2} \\\\ &= \\dfrac{7}{10} . \\dfrac{1}{2} + \\dfrac{11}{8} . \\dfrac{1}{2} \\\\ &= \\dfrac{7 . 1}{10 . 2} + \\dfrac{11 . 1}{8 . 2} \\\\ &= \\dfrac{7}{20} + \\dfrac{11}{16} \\\\ &= \\dfrac{28}{80} + \\dfrac{55}{80} \\\\ &= \\dfrac{83}{80} \\end{align*} $"}]}],"id_ques":1669},{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["-45"],["98"]]],"list":[{"point":5,"width":50,"ques":" \u00c1p d\u1ee5ng t\u00ednh ch\u1ea5t ph\u00e2n ph\u1ed1i c\u1ee7a ph\u00e9p nh\u00e2n \u0111\u1ed1i v\u1edbi ph\u00e9p c\u1ed9ng, h\u00e3y t\u00ednh gi\u00e1 tr\u1ecb bi\u1ec3u th\u1ee9c sau: <br\/><br\/> $ \\dfrac{3}{-7} . \\left( \\dfrac{11}{22} + \\dfrac{8}{14} \\right)$ = <div class=\"frac123\"><div class=\"ts\">_input_<\/div><div class=\"ms\">_input_<\/div><\/div>","hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> R\u00fat g\u1ecdn c\u00e1c ph\u00e2n s\u1ed1 ch\u01b0a t\u1ed1i gi\u1ea3n <br\/> \u00c1p d\u1ee5ng t\u00ednh ch\u1ea5t ph\u00e2n ph\u1ed1i c\u1ee7a ph\u00e9p nh\u00e2n \u0111\u1ed1i v\u1edbi ph\u00e9p c\u1ed9ng \u0111\u1ec3 nh\u00e2n ph\u00e1 ngo\u1eb7c nh\u01b0 sau: <br\/> $\\left(\\dfrac{a}{b} + \\dfrac{c}{d} \\right) . \\dfrac{e}{f} = \\dfrac{a}{b} . \\dfrac{e}{f} + \\dfrac{c}{d} . \\dfrac{e}{f}$ <\/span> <br\/><br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> Ta c\u00f3: <br\/>$ \\begin{align*} \\dfrac{3}{-7} . \\left( \\dfrac{11}{22} + \\dfrac{8}{14} \\right) &= \\dfrac{-3}{7} . \\left( \\dfrac{1}{2} + \\dfrac{4}{7} \\right) \\\\ &= \\dfrac{-3}{7} . \\dfrac{1}{2} + \\dfrac{-3}{7} . \\dfrac{4}{7} \\\\ &= \\dfrac{-3 . 1}{7 . 2} + \\dfrac{-3 . 4}{7 . 7} \\\\ &= \\dfrac{-3}{14} + \\dfrac{-12}{49} \\\\ &= \\dfrac{-21}{98} + \\dfrac{-24}{98} \\\\ &= \\dfrac{-45}{98} \\end{align*}$"}]}],"id_ques":1670}],"lesson":{"save":0,"level":1}}