{"common":{"save":0,"post_id":"782","level":3,"total":10,"point":10,"point_extra":0},"segment":[{"id":"1271","post_id":"782","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":10,"ques":" <center><img src='img\/2.jpg' \/><\/center> 273 . (1 - 354) - 354 . (1 - 273) = <span class='basic_hoi_black'>?<\/span>","select":["A. 81","B. -81","C. -627","D. 627"],"hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> B\u01b0\u1edbc 1: Th\u1ef1c hi\u1ec7n b\u1ecf ngo\u1eb7c<br\/>B\u01b0\u1edbc 2: Nh\u00f3m c\u00e1c c\u1eb7p t\u00edch c\u00f3 t\u1ed5ng ho\u1eb7c hi\u1ec7u b\u1eb1ng 0 \u0111\u1ec3 th\u1ef1c hi\u1ec7n t\u00ednh nhanh.<\/span> <br\/><br\/><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/>$\\begin{align*}&273 . (1 - 354) - 354 . (1 - 273)\\\\&= 273 - 273 . 354 - (354 - 354 . 273)\\\\&= 273 - 354 . 273 - 354 + 354 . 273\\\\&=(273 - 354) + (354 . 273 - 354 . 273)\\\\&=- (354 - 273) + 0\\\\&= -81\\end{align*}$<br\/>V\u1eady ta ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: <span class='basic_pink'> B. -81<\/span><\/span> <br\/>","column":2}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:14:50"},{"id":"1272","post_id":"782","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":10,"ques":" T\u0129m x, bi\u1ebft:<br\/>18 - 2 (x - 5) = -38","select":["A. x = 23","B. x = -23","C. x = 33","D. x = -33"],"hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> B\u01b0\u1edbc 1: T\u00ecm 2 (x - 5)<br\/>B\u01b0\u1edbc 2: T\u00ecm x - 5<br\/>B\u01b0\u1edbc 3: T\u00ecm x<\/span> <br\/><br\/><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/>$\\begin{align*}18 - 2 (x - 5)&= -38\\\\2 (x - 5)&= 18 - (-38)\\\\2 (x - 5)&= 18 + 38\\\\2(x - 5)&=56\\\\x - 5&= 56 : 2\\\\x - 5&= 28\\\\x&= 28 + 5\\\\x&= 33\\end{align*}$<br\/>V\u1eady ta ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: <span class='basic_pink'> C. x = 33<\/span><\/span> <br\/>","column":2}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:14:50"},{"id":"1273","post_id":"782","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":10,"ques":" T\u00ecm x, bi\u1ebft:<br\/>(x - 5) . (x - 1) = 0","select":["A. x = -5","B. x = -1","C. x = -1 v\u00e0 x = -5","D. x = 1 ho\u1eb7c x = 5"],"hint":"","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/>A . B = 0 th\u00ec A = 0 ho\u1eb7c B = 0<\/span> <br\/><span class='basic_left'><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/>Ta c\u00f3:<br\/>(x - 5) . (x - 1) = 0<br\/>$\\Rightarrow$ x - 5 = 0 ho\u1eb7c x - 1 = 0<br\/>+)<br\/> $\\begin{align*}x - 5&=0\\\\x&= 0 + 5\\\\x&= 5\\end{align*}$<br\/>+)<br\/> $\\begin{align*}x - 1&=0\\\\x&= 0 + 1\\\\x&= 1\\end{align*}$<br\/>V\u1eady ta ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: <span class='basic_pink'> D. x = 1 ho\u1eb7c x = 5<\/span><\/span> <br\/><\/span>","column":2}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:14:50"}]}