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{"common":{"save":0,"post_id":"831","level":3,"total":10,"point":10,"point_extra":0},"segment":[{"id":"2031","post_id":"831","mon_id":"0","chapter_id":"0","question":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","options":{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["4"],["1"]]],"list":[{"point":10,"width":50,"content":"","type_input":"","ques":"Tr\u00ean tia Oy l\u1ea5y hai \u0111i\u1ec3m A, B sao cho OA = 2cm, OB = 6cm. G\u1ecdi M l\u00e0 trung \u0111i\u1ec3m c\u1ee7a \u0111o\u1ea1n th\u1eb3ng OB. T\u00ednh AB, AM. <br\/> \u0110\u00e1p \u00e1n l\u00e0: AB = _input_ cm; AM = _input_ cm","hint":"M l\u00e0 trung \u0111i\u1ec3m c\u1ee7a OB n\u00ean MO = MB = $\\dfrac{OB}{2}$","explain":" T\u00f3m t\u1eaft:<\/span><br\/> Tr\u00ean tia Oy <br\/> OA = 2cm <br\/> OB = 6cm <br\/> M l\u00e0 trung \u0111i\u1ec3m c\u1ee7a OB <br\/> T\u00ednh AM, AB <\/span> <br\/><br\/>B\u00e0i gi\u1ea3i: <\/span><br\/> <center><img src='img\/H616_K101.png' \/><\/center> <br\/> V\u00ec M l\u00e0 trung \u0111i\u1ec3m c\u1ee7a \u0111o\u1ea1n th\u1eb3ng OB n\u00ean: <br\/> MB = OM = $\\dfrac{OB}{2} = \\dfrac{6}{2} = 3$cm <br\/> Tr\u00ean tia Oy c\u00f3 OA = 2cm, OB = 6cm <br\/> V\u00ec 2cm < 6cm n\u00ean OA < OB. Do \u0111\u00f3 \u0111i\u1ec3m A n\u1eb1m gi\u1eefa hai \u0111i\u1ec3m O v\u00e0 B <br\/> $\\begin{align*} OA + AB &= AB \\\\ 2cm + AB &= 6cm \\\\ AB &= 6cm - 2cm \\\\ AB &= 4cm \\end{align*}$ <br\/> Tr\u00ean tia Oy c\u00f3 OA = 2cm, OM = 3cm <br\/> V\u00ec 2cm < 3cm n\u00ean OA < OM <br\/> Do \u0111\u00f3 \u0111i\u1ec3m A n\u1eb1m gi\u1eefa hai \u0111i\u1ec3m O v\u00e0 M <br\/> $\\begin{align*} OA + AM &= OM \\\\ 2cm + AM &= 3cm \\\\ AM &= 3cm - 2cm \\\\ AM &= 1 cm \\end{align*}$ <br\/> V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n l\u00e0: AB = 4cm, AM = 1cm<\/span> <br\/> L\u01b0u \u00fd: V\u1edbi nh\u1eefng b\u00e0i t\u00ednh \u0111\u1ed9 d\u00e0i \u0111o\u1ea1n th\u1eb3ng n\u1ebfu b\u00e0i ch\u01b0a cho \u0111i\u1ec3m n\u00e0o n\u1eb1m gi\u1eefa th\u00ec tr\u01b0\u1edbc ti\u00ean ta ph\u1ea3i ch\u1ec9 ra \u0111i\u1ec3m n\u1eb1m gi\u1eefa r\u1ed3i m\u1edbi \u00e1p d\u1ee5ng t\u00ednh ch\u1ea5t c\u1ed9ng \u0111\u1ed9 d\u00e0i \u0111\u1ec3 t\u00ednh <\/b> <\/span> "}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:14:57"},{"id":"2032","post_id":"831","mon_id":"0","chapter_id":"0","question":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","options":{"time":24,"part":[{"title":"\u0110i\u1ec1n \u0111\u00e1p \u00e1n \u0111\u00fang v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["2"]]],"list":[{"point":10,"width":50,"content":"","type_input":"","ques":"Tr\u00ean tia Ot l\u1ea5y hai \u0111i\u1ec3m A, B sao cho OA = 3cm, OB = 7cm. G\u1ecdi I, K l\u1ea7n l\u01b0\u1ee3t l\u00e0 trung \u0111i\u1ec3m c\u1ee7a \u0111o\u1ea1n th\u1eb3ng OA, OB. T\u00ednh IK. <br\/> \u0110\u00e1p \u00e1n l\u00e0: IK = _input_ cm","hint":"T\u00ednh OI, OK r\u1ed3i t\u00ednh IK","explain":" T\u00f3m t\u1eaft:<\/span><br\/> Tr\u00ean tia Ot <br\/> OA = 3cm <br\/> OB = 7cm <br\/> I l\u00e0 trung \u0111i\u1ec3m c\u1ee7a OA <br\/> K l\u00e0 trung \u0111i\u1ec3m c\u1ee7a OB <br\/> T\u00ednh IK = ? <\/span> <br\/><br\/>B\u00e0i gi\u1ea3i: <\/span><br\/> <center><img src='img\/H616_K102.png' \/><\/center> <br\/> V\u00ec I l\u00e0 trung \u0111i\u1ec3m c\u1ee7a OA n\u00ean OI = IA = $\\dfrac{OA}{2} = \\dfrac{3}{2} = 1,5cm$ <br\/> K l\u00e0 trung \u0111i\u1ec3m c\u1ee7a OB n\u00ean OK = KB = $\\dfrac{OB}{2} = \\dfrac{7}{2} = 3,5cm$ <br\/> Tr\u00ean tia Ot c\u00f3: OI = 1,5cm, OK = 3,5cm <br\/> V\u00ec 1,5cm < 3,5cm n\u00ean OI < OK <br\/> Do \u0111\u00f3 \u0111i\u1ec3m I n\u1eb1m gi\u1eefa hai \u0111i\u1ec3m O v\u00e0 K <br\/> $\\begin{align*} OI + IK &= OK \\\\ 1,5cm + IK &= 3,5cm \\\\ IK &= 3,5cm - 1,5cm \\\\ IK &= 2cm \\end{align*}$ <br\/> V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n l\u00e0: IK = 2cm <\/span> "}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:14:57"},{"id":"2033","post_id":"831","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":10,"ques":"Cho \u0111o\u1ea1n th\u1eb3ng AB = 4cm, I l\u00e0 trung \u0111i\u1ec3m c\u1ee7a \u0111o\u1ea1n th\u1eb3ng AB. Tr\u00ean tia \u0111\u1ed1i c\u1ee7a tia AI l\u1ea5y \u0111i\u1ec3m C sao cho AC = 1cm. Tr\u00ean tia \u0111\u1ed1i c\u1ee7a tia BI l\u1ea5y \u0111i\u1ec3m D sao cho BD = 1cm. Kh\u1eb3ng \u0111\u1ecbnh n\u00e0o sau \u0111\u00e2y \u0111\u00fang.","select":["A. I l\u00e0 trung \u0111i\u1ec3m c\u1ee7a CD","B. D l\u00e0 trung \u0111i\u1ec3m c\u1ee7a BI","C. C l\u00e0 trung \u0111i\u1ec3m c\u1ee7a AI","D. B l\u00e0 trung \u0111i\u1ec3m c\u1ee7a ID"],"hint":"V\u1ebd h\u00ecnh, quan s\u00e1t h\u00ecnh v\u1ebd \u0111\u1ec3 l\u1eadp lu\u1eadn ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","explain":" B\u00e0i gi\u1ea3i:<\/span> <br\/> <center><img src='img\/H616_K105.png' \/><\/center> <br\/> V\u00ec I l\u00e0 trung \u0111i\u1ec3m c\u1ee7a \u0111o\u1ea1n th\u1eb3ng AB n\u00ean $AI = IB = \\dfrac{AB}{2} = \\dfrac{4}{2} = 2cm$ <br\/> Tia IA v\u00e0 IB l\u00e0 hai tia \u0111\u1ed1i nhau (1) <br\/> C thu\u1ed9c tia \u0111\u1ed1i c\u1ee7a tia AI n\u00ean A, C n\u1eb1m c\u00f9ng ph\u00eda \u0111\u1ed1i v\u1edbi \u0111i\u1ec3m I (2) <br\/> D thu\u1ed9c tia \u0111\u1ed1i c\u1ee7a tia IB n\u00ean B, D n\u1eb1m c\u00f9ng ph\u00eda \u0111\u1ed1i v\u1edbi \u0111i\u1ec3m I (3) <br\/> T\u1eeb (1), (2) v\u00e0 (3) $\\Rightarrow$ IC v\u00e0 ID l\u00e0 hai tia \u0111\u1ed1i nhau hay \u0111i\u1ec3m I n\u1eb1m gi\u1eefa hai \u0111i\u1ec3m C v\u00e0 D (4)<br\/> V\u00ec C thu\u1ed9c tia \u0111\u1ed1i c\u1ee7a tia AI n\u00ean \u0111i\u1ec3m A n\u1eb1m gi\u1eefa hai \u0111i\u1ec3m C v\u00e0 I <br\/> $\\begin{align*} CI &= AC + AI \\\\ CI &= 1cm + 2cm \\\\ CI &= 3cm \\end{align*}$ <br\/> D thu\u1ed9c tia \u0111\u1ed1i c\u1ee7a tia BI n\u00ean \u0111i\u1ec3m B n\u1eb1m gi\u1eefa hai \u0111i\u1ec3m D v\u00e0 I <br\/> $\\begin{align*} DI &= BI + BD \\\\ DI &= 2cm + 1cm \\\\ DI &= 3cm \\end{align*}$ <br\/> V\u00ec CI = 3cm, DI = 3cm m\u00e0 3cm = 3cm n\u00ean CI = DI (5) <br\/> T\u1eeb (4) v\u00e0 (5) $\\Rightarrow$ \u0110i\u1ec3m I l\u00e0 trung \u0111i\u1ec3m c\u1ee7a \u0111o\u1ea1n th\u1eb3ng CD <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: A <\/span> ","column":2}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:14:57"}]}