{"common":{"save":0,"post_id":"948","level":1,"total":20,"point":5,"point_extra":0},"segment":[{"id":"611","post_id":"948","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":[[1]],"list":[{"point":5,"ques":" C\u00e1c m\u00e1y c\u00e0y c\u00f3 c\u00f9ng n\u0103ng su\u1ea5t c\u00e0y tr\u00ean c\u00e1c c\u00e1nh \u0111\u1ed3ng c\u00f3 c\u00f9ng di\u1ec7n t\u00edch th\u00ec: ","select":["A. S\u1ed1 m\u00e1y t\u1ec9 l\u1ec7 ngh\u1ecbch v\u1edbi s\u1ed1 ng\u00e0y ho\u00e0n th\u00e0nh c\u00f4ng vi\u1ec7c. ","B. S\u1ed1 m\u00e1y t\u1ec9 l\u1ec7 thu\u1eadn v\u1edbi s\u1ed1 ng\u00e0y ho\u00e0n th\u00e0nh c\u00f4ng vi\u1ec7c.","C. S\u1ed1 m\u00e1y kh\u00f4ng t\u1ec9 l\u1ec7 v\u1edbi s\u1ed1 ng\u00e0y ho\u00e0n th\u00e0nh c\u00f4ng vi\u1ec7c. "],"explain":" V\u1edbi c\u00f9ng n\u0103ng su\u1ea5t v\u00e0 di\u1ec7n t\u00edch l\u00e0m vi\u1ec7c th\u00ec s\u1ed1 m\u00e1y c\u00e0y t\u0103ng l\u00ean th\u00ec s\u1ed1 ng\u00e0y ho\u00e0n th\u00e0nh c\u00f4ng vi\u1ec7c s\u1ebd gi\u1ea3m xu\u1ed1ng. <br\/> V\u1eady s\u1ed1 m\u00e1y v\u00e0 s\u1ed1 ng\u00e0y ho\u00e0n th\u00e0nh c\u00f4ng vi\u1ec7c l\u00e0 quan h\u1ec7 t\u1ec9 l\u1ec7 ngh\u1ecbch <br\/><br\/><span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 A. <\/span><\/span> ","column":1}]}]},"correct":"","level":"1","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:22:49"},{"id":"612","post_id":"948","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":[[2]],"list":[{"point":5,"ques":"B\u1ea3ng n\u00e0o d\u01b0\u1edbi \u0111\u00e2y cho ta quan h\u1ec7 t\u1ec9 l\u1ec7 ngh\u1ecbch? <br\/> B\u1ea3ng 1. <table> <tr> <td> $x$<\/td> <td> 1 <\/td> <td> 2 <\/td> <td> 3<\/td> <td> 4 <\/td><\/tr> <tr> <td> $y$<\/td> <td> 1 <\/td> <td> 4<\/td> <td> 9<\/td> <td> 16 <\/td><\/tr> <\/table> B\u1ea3ng 2 . <table> <tr> <td> $x$<\/td> <td> 1 <\/td> <td> 2 <\/td> <td> 3<\/td> <td> 4 <\/td><\/tr> <tr> <td> $y$<\/td> <td> -6 <\/td> <td> -3<\/td> <td> -2<\/td> <td> $-1\\frac{1}{2}$ <\/td><\/tr> <\/table> ","select":["B\u1ea3ng 1","B\u1ea3ng 2"],"hint":"Xem \u0111\u1ecbnh ngh\u0129a t\u1ec9 l\u1ec7 ngh\u1ecbch. ","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> * N\u1ebfu \u0111\u1ea1i l\u01b0\u1ee3ng $y$ li\u00ean h\u1ec7 v\u1edbi \u0111\u1ea1i l\u01b0\u1ee3ng $x$ theo c\u00f4ng th\u1ee9c $y = \\dfrac{a}{x} $ hay $xy = a$ (a l\u00e0 m\u1ed9t h\u1eb1ng s\u1ed1 kh\u00e1c 0) th\u00ec ta n\u00f3i $y$ t\u1ec9 l\u1ec7 ngh\u1ecbch v\u1edbi $x$ theo h\u1ec7 s\u1ed1 t\u1ec9 l\u1ec7 a. <\/span> <br\/><br\/><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> T\u1eeb b\u1ea3ng 1 ta th\u1ea5y $xy = 1.1 \\neq 2.4 \\neq $$ 3.9 \\neq 4.16 $ <br\/> Suy ra $x$ v\u00e0 $y$ kh\u00f4ng l\u00e0 quan h\u1ec7 t\u1ec9 l\u1ec7 ngh\u1ecbch. <br\/> T\u1eeb b\u1ea3ng 2 ta th\u1ea5y $xy = 1.(-6) = 2.(-3) = $$ 3.(-2) = 4.\\left( -1\\dfrac{1}{2} \\right) = -6$ <br\/> Suy ra $x$ v\u00e0 $y$ l\u00e0 quan h\u1ec7 t\u1ec9 l\u1ec7 ngh\u1ecbch. <br\/><br\/><span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 B\u1ea3ng 2. <\/span><\/span> ","column":2}]}]},"correct":"","level":"1","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:22:49"},{"id":"613","post_id":"948","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 ch\u1ea1y t\u1eeb A \u0111\u1ebfn B v\u1edbi v\u1eadn t\u1ed1c 60 km\/h th\u00ec h\u1ebft 2,5 gi\u1edd. L\u00fac t\u1eeb B v\u1ec1 A, xe ch\u1ea1y v\u1edbi v\u1eadn t\u1ed1c 50 km\/h th\u00ec m\u1ea5t bao l\u00e2u? <\/span>","select":["A. 2 gi\u1edd ","B. 2 gi\u1edd 15 ph\u00fat ","C. 2 gi\u1edd 30 ph\u00fat ","D. 3 gi\u1edd "],"hint":"V\u1eadn t\u1ed1c v\u00e0 th\u1eddi gian l\u00e0 hai \u0111\u1ea1i l\u01b0\u1ee3ng t\u1ec9 l\u1ec7 ngh\u1ecbch","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 ( $\\dfrac{x_{1}}{x_{2}} = \\dfrac{y_{2}}{y_{1}} $) <br\/><br\/>T\u00f3m t\u1eaft \u0111\u1ec1 b\u00e0i: <br\/> V\u1eadn t\u1ed1c $ \\hspace{1cm} $ Th\u1eddi gian <br\/> 60 km\/h $ \\hspace{1cm} $ 2,5 gi\u1edd <br\/> 50 km\/h $ \\hspace{1cm} $ $x$ gi\u1edd? <br\/><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> Tr\u00ean c\u00f9ng m\u1ed9t qu\u00e3ng \u0111\u01b0\u1eddng, v\u1eadn t\u1ed1c v\u00e0 th\u1eddi gian l\u00e0 hai \u0111\u1ea1i l\u01b0\u1ee3ng t\u1ec9 l\u1ec7 ngh\u1ecbch. <br\/> Theo t\u00ednh ch\u1ea5t c\u1ee7a hai \u0111\u1ea1i l\u01b0\u1ee3ng t\u1ec9 l\u1ec7 ngh\u1ecbch, ta c\u00f3: <br\/> $\\dfrac{60}{50} = \\dfrac{x}{2,5} \\Rightarrow x = \\dfrac{60.2,5}{50} = 3 $ <br\/> V\u1eady th\u1eddi gian xe ch\u1ea1y t\u1eeb B v\u1ec1 A l\u00e0 3 gi\u1edd. <br\/><span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 D. <\/span><\/span> ","column":2}]}]},"correct":"","level":"1","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:22:49"}]}