{"common":{"save":0,"post_id":"1006","level":3,"total":10,"point":10,"point_extra":0},"segment":[{"id":"1781","post_id":"1006","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":[[["75"],["15"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","hint":"T\u00ednh $\\widehat{ADH} \\to \\widehat{BAD} \\to \\widehat{B} \\to \\widehat{C}$","ques":" <span class='basic_left'> Cho tam gi\u00e1c $ABC$ c\u00f3 $\\widehat{B} > \\widehat{C} $. K\u1ebb $AH$ vu\u00f4ng g\u00f3c v\u1edbi $BC$ t\u1ea1i H, k\u1ebb \u0111\u01b0\u1eddng ph\u00e2n gi\u00e1c $AD$ c\u1ee7a g\u00f3c $\\widehat{A} $ ($D\\in BC$). Bi\u1ebft $\\widehat{HAD} = 30^{o} $ v\u00e0 $\\widehat{A} = 90^{o} $ <br\/> T\u00ednh s\u1ed1 \u0111o g\u00f3c $B$ v\u00e0 g\u00f3c $C$. <br\/> <b> \u0110\u00e1p \u00e1n: <\/b> <br\/> $\\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} $ <\/span> ","explain":"<span class='basic_left'> <span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b> T\u00ednh $\\widehat{ADH}$ trong $\\Delta ADH$ <br\/> <b> B\u01b0\u1edbc 2: <\/b> T\u00ednh $\\widehat{BAD}$ <br\/> <b> B\u01b0\u1edbc 3: <\/b> T\u00ednh $\\widehat{B}$ trong $\\Delta ABD$ <br\/> <b> B\u01b0\u1edbc 4: <\/b> T\u00ednh $\\widehat{C}$ <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> <center><img src='img\/H7B16-26.png' \/> <\/center> * Tam gi\u00e1c $AHD$ vu\u00f4ng t\u1ea1i H n\u00ean $\\widehat{HAD} + \\widehat{ADH} = 90^{o} $ <br\/> $\\Rightarrow \\widehat{ADH} = 90^{o} - \\widehat{HAD} = 90^{o} - 30^{o} = 60^{o} $ hay $\\widehat{ADB} = 60^{o} $ <br\/> * AD l\u00e0 ph\u00e2n gi\u00e1c c\u1ee7a g\u00f3c A n\u00ean $\\widehat{BAD} = \\dfrac{\\widehat{A}}{2} = \\dfrac{90^{o}}{2} = 45^{o} $ <br\/> *Tam gi\u00e1c ABD c\u00f3 $\\widehat{BAD} + \\widehat{B} + \\widehat{ADB} = 180^{o} \\\\ \\Leftrightarrow 45^{o} + \\widehat{B} + 60^{o} = 180^{o} \\\\ \\Leftrightarrow \\widehat{B} = 75^{o} $ <br\/> *Tam gi\u00e1c ABC vu\u00f4ng t\u1ea1i A n\u00ean $\\widehat{B} + \\widehat{C} = 90^{o} $ <br\/> m\u00e0 $\\widehat{B} = 75^{o} $ n\u00ean $\\widehat{C} = 90^{o} - 75^{o} = 15^{o}$ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u1ea7n l\u01b0\u1ee3t l\u00e0: 75 v\u00e0 15<\/span><\/span> <br\/>"}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:23:03"},{"id":"1782","post_id":"1006","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":[[["80"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","ques":" <span class='basic_left'>Cho tam gi\u00e1c $ABC$, bi\u1ebft $\\widehat{A} = 3\\widehat{B} $ v\u00e0 $\\widehat{B} = 2\\widehat{C} $ <br\/> G\u1ecdi E l\u00e0 giao \u0111i\u1ec3m c\u1ee7a \u0111\u01b0\u1eddng th\u1eb3ng $AB$ v\u1edbi ph\u00e2n gi\u00e1c g\u00f3c ngo\u00e0i \u1edf \u0111\u1ec9nh C c\u1ee7a tam gi\u00e1c $ABC$. <br\/> S\u1ed1 \u0111o g\u00f3c $\\widehat{ACE} $ l\u00e0: $\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^o$ <\/span> ","explain":"<span class='basic_left'> <span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b> T\u00ednh $\\widehat{A}$ v\u00e0 $\\widehat{B}$ trong $\\Delta ABC$ <br\/> <b> B\u01b0\u1edbc 2: <\/b> T\u00ednh $\\widehat{CAx}$ l\u00e0 g\u00f3c ngo\u00e0i $\\Delta ABC$ <br\/> <b> B\u01b0\u1edbc 3: <\/b> T\u00ednh $\\widehat{ACE}$ theo t\u00ednh ch\u1ea5t ph\u00e2n gi\u00e1c <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> <center><img src='img\/H7B16-27.png' \/> <\/center> <span class='basic_left'> Tam gi\u00e1c $ABC$ c\u00f3: $\\widehat{A} = 3\\widehat{B} $ v\u00e0 $\\widehat{B} = 2\\widehat{C} $ n\u00ean $\\widehat{A} = 3.2\\widehat{C} = 6\\widehat{C} $<br\/> Do $\\widehat{A} + \\widehat{B} + \\widehat{C} = 180^{o} \\\\ \\Rightarrow 6\\widehat{C} + 2\\widehat{C} + \\widehat{C} = 180^{o} \\\\ \\Leftrightarrow 9\\widehat{C} = 180^{o} \\\\ \\Rightarrow \\widehat{C} = 20^{o} \\\\ \\Rightarrow \\widehat{A} = 6.20^{o} = 120^{o}; \\widehat{B} = 2.20^{o} = 40^{o} $ <br\/> Tam gi\u00e1c $ABC$ c\u00f3: $\\widehat{ACx} = \\widehat{A} + \\widehat{B} $ (g\u00f3c ngo\u00e0i c\u1ee7a tam gi\u00e1c) <br\/> $\\Rightarrow \\widehat{ACx} = 120^{o} + 40^{o} = 160^{o} $ <br\/> CE l\u00e0 tia ph\u00e2n gi\u00e1c c\u1ee7a $\\widehat{ACx} $ n\u00ean: $\\widehat{ACE} = \\dfrac{1}{2}\\widehat{ACx} = \\dfrac{1}{2}.160^{o} = 80^{o} $ <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0: 80<\/span><\/span> <br\/>"}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:23:03"},{"id":"1783","post_id":"1006","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":[[["11"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","ques":" <span class='basic_left'> Cho $\\triangle ABC = \\triangle MNP $. <br\/> Bi\u1ebft $AB + BC = 7cm, MN - NP = 3cm, MP = 4cm.$ <br\/> Chu vi tam gi\u00e1c $ABC$ l\u00e0: $\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}(cm)$ ","explain":"<span class='basic_left'> <span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b> T\u00ednh \u0111\u1ed9 d\u00e0i $AC$ theo t\u00ednh ch\u1ea5t hai tam gi\u00e1c $ABC$ v\u00e0 $MNP$ b\u1eb1ng nhau <br\/> <b> B\u01b0\u1edbc 2: <\/b> T\u00ednh $AB$ v\u00e0 $BC$ khi bi\u1ebft t\u1ed5ng v\u00e0 hi\u1ec7u <br\/> <b> B\u01b0\u1edbc 3: <\/b> T\u00ednh chu vi $\\Delta ABC$ <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span> <br\/> Ta c\u00f3: $\\triangle ABC = \\triangle MNP $ <br\/> $\\Rightarrow$ $AB = MN, BC = NP, AC = MP$ (c\u00e1c c\u1eb7p c\u1ea1nh t\u01b0\u01a1ng \u1ee9ng) <br\/> M\u00e0 $MN - NP = 3cm$ $\\Rightarrow$ $ AB - BC = 3cm$ <br\/> Theo b\u00e0i c\u00f3 $AB + BC = 7cm$ <br\/> Suy ra: $2AB = 10cm$ $\\Rightarrow $ $AB = 5cm$ <br\/> $\\Rightarrow $ $BC = 7 - AC = 2cm$ <br\/> Do \u0111\u00f3 ta c\u00f3: $AB = 5cm, BC = 2cm, AC = 4cm$ <br\/> V\u1eady chu vi tam gi\u00e1c $ABC$ b\u1eb1ng: <br\/> $AB + BC + AC = 5 + 2 + 4 = 11cm$ <br\/><br\/><span class='basic_pink'>\u0110\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0: 11 <\/span> "}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:23:03"}]}