{"common":{"save":0,"post_id":"950","level":2,"total":20,"point":5,"point_extra":0},"segment":[{"id":"631","post_id":"950","mon_id":"0","chapter_id":"0","question":"T\u00edch v\u00e0o \u00f4 \u0111\u00fang","options":{"time":24,"part":[{"title":"T\u00edch v\u00e0o \u00f4 \u0111\u00fang","title_trans":"","temp":"true_false","correct":[["t","f","f","f"]],"list":[{"point":5,"image":"","col_name":["Kh\u1eb3ng \u0111\u1ecbnh","\u0110\u00fang","Sai"],"arr_ques":["Th\u1eddi gian \u0111\u1ec3 m\u1ed9t \u00f4 t\u00f4 v\u01b0\u1ee3t qua qu\u00e3ng \u0111\u01b0\u1eddng AB t\u1ec9 l\u1ec7 ngh\u1ecbch v\u1edbi v\u1eadn t\u1ed1c c\u1ee7a \u00f4 t\u00f4 \u0111\u00f3","Chu vi c\u1ee7a m\u1ed9t h\u00ecnh vu\u00f4ng t\u1ec9 l\u1ec7 ngh\u1ecbch v\u1edbi \u0111\u1ed9 d\u00e0i c\u1ee7a c\u1ea1nh h\u00ecnh vu\u00f4ng \u0111\u00f3","\u0110\u1ea1i l\u01b0\u1ee3ng A t\u1ec9 l\u1ec7 ngh\u1ecbch v\u1edbi \u0111\u1ea1i l\u01b0\u1ee3ng B th\u00ec khi A gi\u1ea3m B c\u0169ng gi\u1ea3m","\u0110\u1ea1i l\u01b0\u1ee3ng A t\u1ec9 l\u1ec7 ngh\u1ecbch v\u1edbi \u0111\u1ea1i l\u01b0\u1ee3ng B th\u00ec khi A t\u0103ng B c\u0169ng t\u0103ng"],"explain":["Tr\u00ean qu\u00e3ng \u0111\u01b0\u1eddng AB, n\u1ebfu v\u1eadn t\u1ed1c t\u0103ng l\u00ean th\u00ec th\u1eddi gian \u0111i h\u1ebft qu\u00e3ng \u0111\u01b0\u1eddng gi\u1ea3m xu\u1ed1ng v\u00e0 ng\u01b0\u1ee3c l\u1ea1i. V\u1eady \u0111\u00e2y l\u00e0 quan h\u1ec7 t\u1ec9 l\u1ec7 ngh\u1ecbch.","<br\/>Chu vi h\u00ecnh vu\u00f4ng b\u1eb1ng \u0111\u1ed9 d\u00e0i m\u1ed9t c\u1ea1nh nh\u00e2n 4, n\u00ean \u0111\u1ed9 d\u00e0i c\u1ea1nh h\u00ecnh vu\u00f4ng t\u0103ng l\u00ean th\u00ec chu vi h\u00ecnh vu\u00f4ng c\u0169ng t\u0103ng. V\u1eady \u0111\u00e2y l\u00e0 quan h\u1ec7 t\u1ec9 l\u1ec7 thu\u1eadn.","<br\/>\u0110\u1ea1i l\u01b0\u1ee3ng A t\u1ec9 l\u1ec7 ngh\u1ecbch v\u1edbi \u0111\u1ea1i l\u01b0\u1ee3ng B th\u00ec A gi\u1ea3m l\u00e0m \u0111i cho B t\u0103ng l\u00ean v\u00e0 ng\u01b0\u1ee3c l\u1ea1i."]}]}]},"correct":"","level":"2","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:22:49"},{"id":"632","post_id":"950","mon_id":"0","chapter_id":"0","question":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","options":{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":" <span class='basic_left'>M\u1ed9t \u00f4 t\u00f4 \u0111i t\u1eeb A \u0111\u1ebfn B v\u1edbi v\u1eadn t\u1ed1c 50 km\/h v\u00e0 tr\u1edf v\u1ec1 A v\u1edbi v\u1eadn t\u1ed1c 60 km\/h. Bi\u1ebft th\u1eddi gian v\u1ec1 \u00edt h\u01a1n th\u1eddi gian \u0111i l\u00e0 30 ph\u00fat. T\u00ednh th\u1eddi gian \u0111i t\u1eeb A \u0111\u1ebfn B r\u1ed3i quay l\u1ea1i A?<\/span>","select":["A. 4 gi\u1edd ","B. 4,5 gi\u1edd","C. 5 gi\u1edd","D. 5,5 gi\u1edd "],"explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> X\u00e1c \u0111\u1ecbnh quan h\u1ec7 t\u1ec9 l\u1ec7 ngh\u1ecbch gi\u1eefa hai \u0111\u1ea1i l\u01b0\u1ee3ng. <br\/> Theo t\u00ednh ch\u1ea5t c\u1ee7a hai \u0111\u1ea1i l\u01b0\u1ee3ng t\u1ec9 l\u1ec7 ngh\u1ecbch l\u1eadp c\u00e1c t\u1ec9 s\u1ed1 b\u1eb1ng nhau $\\left(\\dfrac{x_{1}}{x_{2}} = \\dfrac{y_{2}}{y_{1}}\\right) $ <br\/><br\/><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> <span class='basic_left'> \u0110\u1ed5i: 30 ph\u00fat = $\\dfrac{1}{2}$ (gi\u1edd) <br\/> Gi\u1ea3 s\u1eed \u00f4 t\u00f4 \u0111i t\u1eeb A \u0111\u1ebfn B v\u1edbi v\u1eadn t\u1ed1c 50 km\/h v\u1edbi th\u1eddi gian l\u00e0 $t_{1}$ (gi\u1edd), $t_{1} > 0$ <br\/> \u00d4 t\u00f4 tr\u1edf v\u1ec1 t\u1eeb B t\u1edbi A v\u1edbi v\u1eadn t\u1ed1c 60 km\/h v\u1edbi th\u1eddi gian l\u00e0 $t_{2}$ (gi\u1edd), $t_{2} > 0$ <br\/> Theo gi\u1ea3 thi\u1ebft c\u00f3: $t_{1} - t_{2} = \\dfrac{1}{2} $ <br\/> Tr\u00ean c\u00f9ng qu\u00e3ng \u0111\u01b0\u1eddng th\u00ec th\u1eddi gian v\u00e0 v\u1eadn t\u1ed1c l\u00e0 hai \u0111\u1ea1i l\u01b0\u1ee3ng t\u1ec9 l\u1ec7 ngh\u1ecbch n\u00ean ta c\u00f3: <br\/> $ \\dfrac{50}{60} = \\dfrac{t_{2}}{t_{1}} \\Leftrightarrow \\dfrac{t_{1}}{6} = \\dfrac{t_{2}}{5} = \\dfrac{t_{1} - t_{2}}{6-5} = \\dfrac{\\dfrac{1}{2}}{1} = \\dfrac{1}{2} \\\\ \\Rightarrow t_{1} = 6.\\dfrac{1}{2} = 3 \\\\ t_{2} = 5.\\dfrac{1}{2} = 2,5 $ <br\/> V\u1eady th\u1eddi gian \u0111i t\u1eeb A \u0111\u1ebfn B r\u1ed3i quay l\u1ea1i A l\u00e0 : $t_{1} + t_{2} = 3 + 2,5 = 5,5 $ (gi\u1edd) <br\/><span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 D. <\/span><\/span> ","column":2}]}]},"correct":"","level":"2","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:22:49"},{"id":"633","post_id":"950","mon_id":"0","chapter_id":"0","question":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","options":{"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":"Bi\u1ebft $x, y$ l\u00e0 hai \u0111\u1ea1i l\u01b0\u1ee3ng t\u1ec9 l\u1ec7 ngh\u1ecbch v\u00e0 c\u00f3 c\u00e1c gi\u00e1 tr\u1ecb t\u01b0\u01a1ng \u1ee9ng cho \u1edf b\u1ea3ng sau: <table><tr><td> x<\/td> <td> 4 <\/td> <td> 8<\/td><\/tr> <tr><td> y <\/td> <td> 6 <\/td> <td> ? <\/td><\/tr> <\/table> K\u1ebft qu\u1ea3 \u1edf \u00f4 tr\u1ed1ng l\u00e0: ","select":["A. 16","B. 24","C. 3","D. -36 "],"hint":"X\u00e1c \u0111\u1ecbnh h\u1ec7 s\u1ed1 t\u1ec9 l\u1ec7 $a = xy$, sau \u0111\u00f3 thay v\u00e0o r\u1ed3i t\u00ecm $y$.","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> X\u00e1c \u0111\u1ecbnh h\u1ec7 s\u1ed1 t\u1ec9 l\u1ec7 a, v\u1edbi $a = xy$ <br\/> T\u00ecm $y$ theo c\u00f4ng th\u1ee9c: $ y = \\dfrac{a}{x} $ <\/span> <br\/><br\/><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> V\u00ec $y$ v\u00e0 $x$ l\u00e0 hai \u0111\u1ea1i l\u01b0\u1ee3ng t\u1ec9 l\u1ec7 ngh\u1ecbch n\u00ean h\u1ec7 s\u1ed1 t\u1ec9 l\u1ec7 $ a = xy = 4.6 = 24$ <br\/> Khi $x = 8$ th\u00ec $ y = \\dfrac{a}{x} = \\dfrac{24}{8} = 3$ <br\/><br\/><span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 C. <\/span><\/span> ","column":4}]}]},"correct":"","level":"2","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:22:49"}]}