{"common":{"save":0,"post_id":"975","level":3,"total":10,"point":10,"point_extra":0},"segment":[{"id":"1571","post_id":"975","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 c\u00e2u tr\u1ea3 l\u1eddi sai. ","select":["A. G\u00f3c ngo\u00e0i c\u1ee7a tam gi\u00e1c l\u00e0 g\u00f3c k\u1ec1 b\u00f9 v\u1edbi m\u1ed9t g\u00f3c c\u1ee7a tam gi\u00e1c.","B. M\u1ed7i g\u00f3c ngo\u00e0i c\u1ee7a tam gi\u00e1c b\u1eb1ng t\u1ed5ng hai g\u00f3c trong kh\u00f4ng k\u1ec1 v\u1edbi n\u00f3.","C. G\u00f3c ngo\u00e0i c\u1ee7a m\u1ed9t tam gi\u00e1c l\u1edbn h\u01a1n m\u1ed7i g\u00f3c trong kh\u00f4ng k\u1ec1 v\u1edbi n\u00f3.","D. T\u1ed5ng c\u00e1c g\u00f3c ngo\u00e0i t\u1ea1i ba \u0111\u1ec9nh c\u1ee7a m\u1ed9t tam gi\u00e1c b\u1eb1ng $ 180^{o}$ "],"explain":" <span class='basic_left'> <span class='basic_pink'> \u0110\u00e1p \u00e1n sai l\u00e0 D. V\u00ec: <\/span><br\/> G\u1ecdi $\\widehat{A_{1}}, \\widehat{B_{1}}, \\widehat{C_{1}} $ theo th\u1ee9 t\u1ef1 l\u00e0 c\u00e1c g\u00f3c ngo\u00e0i t\u1ea1i c\u00e1c \u0111\u1ec9nh A, B, C c\u1ee7a tam gi\u00e1c ABC. <br\/> Ta c\u00f3 $\\widehat{A_{1}} + \\widehat{A} = 180^{o}, \\widehat{B_{1}} + \\widehat{B} = 180^{o}, \\widehat{C_{1}} + \\widehat{C} = 180^{o} \\\\ \\Rightarrow (\\widehat{A_{1}} + \\widehat{B_{1}} + \\widehat{C_{1}}) + (\\widehat{A} + \\widehat{B} + \\widehat{C} ) = 180^{o} + 180^{o} + 180^{o} = 540^{o}$ <br\/> m\u00e0 $\\widehat{A} + \\widehat{B} + \\widehat{C} = 180^{o} $ <br\/> Suy ra $\\widehat{A_{1}} + \\widehat{B_{1}} + \\widehat{C_{1}} = 540^{o} - 180^{o} = 360^{o} $ <\/span> ","column":1}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:23:01"},{"id":"1572","post_id":"975","mon_id":"0","chapter_id":"0","question":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","options":{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["60"],["40"],["80"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","ques":" <span class='basic_left'> T\u00ednh c\u00e1c g\u00f3c c\u1ee7a tam gi\u00e1c $ABC$ bi\u1ebft: $4\\widehat{A} = 6\\widehat{B} = 3\\widehat{C} $ <br\/> <b> \u0110\u00e1p \u00e1n: <\/b> <br\/> $\\widehat{A} = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^{o} \\\\ \\widehat{B} = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^{o} \\\\ \\widehat{C} = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^{o} $ ","explain":" <span class='basic_left'>X\u00e9t tam gi\u00e1c ABC c\u00f3: $\\widehat{A} + \\widehat{B} + \\widehat{C} = 180^{o} $ (1) <br\/> Ta c\u00f3: $4\\widehat{A} = 6\\widehat{B} = 3\\widehat{C} $ (gi\u1ea3 thi\u1ebft) <br\/> $\\Rightarrow \\dfrac{4\\widehat{A}}{12} = \\dfrac{6\\widehat{B}}{12} = \\dfrac{3\\widehat{C}}{12} \\Rightarrow \\dfrac{\\widehat{A}}{3} = \\dfrac{\\widehat{B}}{2} = \\dfrac{\\widehat{C}}{4} $ (2) <br\/> T\u1eeb (1) v\u00e0 (2), \u00e1p d\u1ee5ng t\u00ednh ch\u1ea5t d\u00e3y t\u1ec9 s\u1ed1 b\u1eb1ng nhau ta c\u00f3: <br\/> $ \\dfrac{\\widehat{A}}{3} = \\dfrac{\\widehat{B}}{2} = \\dfrac{\\widehat{C}}{4} = \\dfrac{\\widehat{A}+\\widehat{B}+\\widehat{C}}{3+2+4} = \\dfrac{180^{o}}{9} = 20^{o} $ <br\/> Suy ra $\\widehat{A} = 20^{o}.3 = 60^{o} \\\\ \\widehat{B} = 20^{o}.2 = 40^{o} \\\\ \\widehat{C} = 20^{o}.4 = 80^{o} $ <br\/> <br\/> <span class='basic_pink'> V\u1eady $\\widehat{A} = 60^{o} \\\\ \\widehat{B} = 40^{o} \\\\ \\widehat{C} = 80^{o} $<\/span><\/span> <br\/>"}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:23:01"},{"id":"1573","post_id":"975","mon_id":"0","chapter_id":"0","question":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","options":{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["45"],["75"],["60"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","ques":"T\u00ednh c\u00e1c g\u00f3c c\u1ee7a tam gi\u00e1c $MNP$ bi\u1ebft: $5\\widehat{M} = 3\\widehat{N}, 7\\widehat{M} - 4\\widehat{N} = 15^{o} $ <br\/> <b> \u0110\u00e1p \u00e1n: <\/b> <br\/> $\\widehat{M} = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^{o} \\\\ \\widehat{N} = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^{o} \\\\ \\widehat{P} = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^{o} $ ","explain":" <span class='basic_left'>Ta c\u00f3: $5\\widehat{M} = 3\\widehat{N}$ (gi\u1ea3 thi\u1ebft) <br\/> $\\Rightarrow \\dfrac{\\widehat{M}}{3} = \\dfrac{\\widehat{N}}{5} $ <br\/> \u00c1p d\u1ee5ng t\u00ednh ch\u1ea5t d\u00e3y t\u1ec9 s\u1ed1 b\u1eb1ng nhau, ta c\u00f3: <br\/> $\\dfrac{\\widehat{M}}{3} = \\dfrac{\\widehat{N}}{5} = \\dfrac{7\\widehat{M}}{21} = \\dfrac{4\\widehat{N}}{20} = \\dfrac{7\\widehat{M} - 4\\widehat{N} }{21-20} = \\dfrac{15^{o}}{1} = 15^{o} $ <br\/> Suy ra $\\widehat{M} = 15^{o}.3 = 45^{o} \\\\ \\widehat{N} = 15^{o}.5 = 75^{o} $ <br\/> X\u00e9t tam gi\u00e1c $MNP$ c\u00f3: $\\widehat{M} + \\widehat{N} + \\widehat{P} = 180^{o} $ <br\/> M\u00e0 $ \\widehat{M} = 45^{o} , \\widehat{N} = 75^{o} $ <br\/> N\u00ean $\\widehat{P} = 180^{o} - (45^{o} + 75^{o} ) = 60^{o} $ <br\/> <span class='basic_pink'> V\u1eady $\\widehat{M} = 45^{o} \\\\ \\widehat{N} = 75^{o} \\\\ \\widehat{P} = 60^{o} $<\/span><\/span> <br\/>"}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:23:01"}]}