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{"segment":[{"part":[{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang ","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":10,"ques":"H\u00e0m s\u1ed1 $y= (2m-6)x+3-2m \\,\\,(m\\ne 3)$ ngh\u1ecbch bi\u1ebfn khi:","select":["A. $m=3$ ","B. $m < 3$","C. $m > 3$ ","D. $m \\ge 3$"],"hint":"H\u00e0m s\u1ed1 $y = ax +b \\,\\,(a\\ne 0)$ \u0111\u1ed3ng bi\u1ebfn n\u1ebfu $a > 0$ v\u00e0 ngh\u1ecbch bi\u1ebfn n\u1ebfu $a < 0$. ","explain":" H\u00e0m s\u1ed1 $y= (2m-6)x+3-2m \\,\\,(m\\ne 3)$ ngh\u1ecbch bi\u1ebfn khi: <br\/>$2m - 6 < 0 \\Leftrightarrow m < 3$<br\/> <span class='basic_pink'>\u0110\u00e1p \u00e1n l\u00e0 B.<\/span>","column":4}],"id_ques":201},{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["1"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","type_check":"","ques":"\u0110\u01b0\u1eddng th\u1eb3ng $(m-1)x+(m+1)y=3$ song song v\u1edbi tr\u1ee5c ho\u00e0nh c\u1ee7a h\u1ec7 tr\u1ee5c t\u1ecda \u0111\u1ed9 $Oxy$ khi $m=$ _input_","hint":"Hai \u0111\u01b0\u1eddng th\u1eb3ng song song khi h\u1ec7 s\u1ed1 g\u00f3c b\u1eb1ng nhau v\u00e0 tung \u0111\u1ed9 g\u1ed1c kh\u00e1c nhau.","explain":"<span class='basic_left'> Tr\u1ee5c ho\u00e0nh c\u00f3 ph\u01b0\u01a1ng tr\u00ecnh $y= 0$ n\u00ean h\u1ec7 s\u1ed1 g\u00f3c b\u1eb1ng $0$. <br\/>\u0110\u01b0\u1eddng th\u1eb3ng $(m-1)x+(m+1)y=3$ hay $y=\\dfrac{1-m}{m+1}x+\\dfrac{3}{m+1}$ song song v\u1edbi tr\u1ee5c ho\u00e0nh c\u1ee7a h\u1ec7 tr\u1ee5c t\u1ecda \u0111\u1ed9 $Oxy$ <br\/>$\\Leftrightarrow 1-m = 0\\Leftrightarrow m = 1$<br\/><span class='basic_pink'>V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n l\u00e0 $1$.<\/span>"}],"id_ques":202},{"title":"V\u1ebd \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y= ax + b$","title_trans":"\u0110\u1ec1 chung cho ba c\u00e2u","temp":"coordinates","correct":[["0,-0.5","1,-2","2,-3.5","3,5","-1,1","-2,2.5"]],"list":[{"point":10,"toa_do":[["-3","4","A"]],"is_click":1,"name_toado_click":"B","draw_line":1,"ques":"Cho \u0111\u01b0\u1eddng th\u1eb3ng $(d):\\, (m - 2)x+(m - 1)y = 1$<br\/><b> C\u00e2u a: <\/b> V\u1ebd \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 v\u1edbi $m = -1$. <br\/>Cho s\u1eb5n $A(-3; 4)$. H\u00e3y click th\u00eam m\u1ed9t \u0111i\u1ec3m thu\u1ed9c \u0111\u1ed3 th\u1ecb \u0111\u1ec3 v\u1ebd \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1.<br\/>_inputduongthang_ ","explain":" <span class='basic_left'> V\u1edbi $m=- 1 \\,\\Rightarrow -3x-2y=1\\,$$ \\Leftrightarrow y =-\\dfrac{3}{2}x-\\dfrac{1}{2}$<br\/>V\u1edbi $x = 0 \\, \\Rightarrow y =-\\dfrac{1}{2}\\Rightarrow B \\left( 0; -\\dfrac{1}{2}\\right)$<br\/> \u0110\u01b0\u1eddng th\u1eb3ng \u0111i qua hai \u0111i\u1ec3m $A;B$ l\u00e0 \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y =-\\dfrac{3}{2}x-\\dfrac{1}{2}$. <br\/><center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/daiso/bai13/lv3/img\/D925_K2a.png' \/><\/center>"}],"id_ques":203},{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"\u0110\u1ec1 chung cho ba c\u00e2u","temp":"fill_the_blank","correct":[[["5"],["3"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","type_check":"","ques":"Cho \u0111\u01b0\u1eddng th\u1eb3ng $(d):\\, (m - 2)x+(m - 1)y = 1$<br\/><b> C\u00e2u b: <\/b> T\u00ecm $m$ \u0111\u1ec3 \u0111\u01b0\u1eddng th\u1eb3ng $(d)$ \u0111i qua \u0111i\u1ec3m $A (1; 2)$.<br\/><b> \u0110\u00e1p s\u1ed1: <\/b>$m=\\dfrac{\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}}{\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}}$","hint":"Thay t\u1ecda \u0111\u1ed9 \u0111i\u1ec3m $A$ v\u00e0o \u0111\u01b0\u1eddng th\u1eb3ng $(d)$ \u0111\u1ec3 t\u00ecm $m$.","explain":"Ta c\u00f3: $A(1; 2) \\in (d)$ <br\/> $\\begin {aligned}& \\Rightarrow (m -2).1 +(m-1).2=1\\\\ & \\Leftrightarrow m- 2 + 2m -2=1\\\\&\\Leftrightarrow m=\\dfrac{5}{3} \\\\ \\end{aligned}$ <br\/><span class='basic_pink'>V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n l\u00e0 $5$ v\u00e0 $3$.<\/span>"}],"id_ques":204},{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"\u0110\u1ec1 chung cho ba c\u00e2u","temp":"fill_the_blank","correct":[[["-1"],["1"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","type_check":"","ques":"Cho \u0111\u01b0\u1eddng th\u1eb3ng $(d):\\, (m - 2)x+(m - 1)y = 1$<br\/><b> C\u00e2u c: <\/b> T\u00ecm \u0111i\u1ec3m c\u1ed1 \u0111\u1ecbnh $I$ m\u00e0 \u0111\u01b0\u1eddng th\u1eb3ng $(d)$ lu\u00f4n \u0111i qua.<br\/><b> \u0110\u00e1p s\u1ed1: <\/b>T\u1ecda \u0111\u1ed9 \u0111i\u1ec3m $I$ l\u00e0 (_input_ ;_input_)","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<br\/><\/span>B\u01b0\u1edbc 1: G\u1ecdi $I(x_{o},y_{o})$ l\u00e0 \u0111i\u1ec3m c\u1ed1 \u0111\u1ecbnh thu\u1ed9c $(d)$. Thay t\u1ecda \u0111\u1ed9 c\u1ee7a \u0111i\u1ec3m $I$ v\u00e0o \u0111\u01b0\u1eddng th\u1eb3ng $(d)$<br\/>B\u01b0\u1edbc 2: Bi\u1ebfn \u0111\u1ed5i ph\u01b0\u01a1ng tr\u00ecnh v\u1ec1 d\u1ea1ng $a.m + b= 0$<br\/>B\u01b0\u1edbc 3: T\u00ecm gi\u00e1 tr\u1ecb c\u1ee7a $m$ r\u1ed3i k\u1ebft lu\u1eadn. <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/>$(d):\\,(m-2)x+(m-1)y=1$<br\/>G\u1ecdi $I \\left( {{x}_{o}};{{y}_{o}} \\right)$ l\u00e0 \u0111i\u1ec3m c\u1ed1 \u0111\u1ecbnh thu\u1ed9c $(d)$<br\/>$\\Rightarrow I\\left( {{x}_{o}};{{y}_{o}} \\right)\\in \\left( d \\right)\\,\\,\\,\\forall m$ <br\/>$ \\left( m-2 \\right){{x}_{o}}+\\left( m-1 \\right){{y}_{o}}=1\\,\\,\\,\\forall m$ <br\/>$ \\Leftrightarrow m{{x}_{o}}-2x_{o}+m{{y}_{o}}-{{y}_{o}}-1=0\\,\\forall m $<br\/>$ \\Leftrightarrow \\left( {{x}_{o}}+{{y}_{o}} \\right)m-\\left( 2{{x}_{o}}+{{y}_{o}}+1 \\right)=0\\,\\forall m$ <br\/>$ \\Leftrightarrow \\left\\{ \\begin{aligned} & {{x}_{o}}+y_{o}=0 \\\\ & 2x_{o}+y_{o}+1=0 \\\\ \\end{aligned} \\right.\\Leftrightarrow \\left\\{ \\begin{aligned} & {{x}_{o}}=-1 \\\\ & {{y}_{o}}=1 \\\\ \\end{aligned} \\right.$ <br\/>$\\Rightarrow I\\left( -1;1 \\right)$ l\u00e0 \u0111i\u1ec3m c\u1ed1 \u0111\u1ecbnh thu\u1ed9c $\\left( d \\right)$ <br\/><span class='basic_pink'>V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n l\u00e0 $-1;1 $<\/span><\/span>"}],"id_ques":205},{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":10,"ques":"\u0110\u01b0\u1eddng th\u1eb3ng \u0111i qua \u0111i\u1ec3m $A (4; -6)$ v\u00e0 vu\u00f4ng g\u00f3c v\u1edbi \u0111\u01b0\u1eddng th\u1eb3ng $y=x - 5$ c\u00f3 ph\u01b0\u01a1ng tr\u00ecnh l\u00e0:","select":["A. $y = -x +3$ ","B. $y = x -8$","C. $y= -2x +2$ ","D. $y= -x -2$"],"hint":"$(d):\\,y= ax + b\\,\\,(a\\ne 0)$ v\u00e0 $(d'):\\, y= a'x+b' \\,\\,(a'\\ne 0)$<br\/>$(d)\\bot (d') \\Leftrightarrow a.a'=-1$ ","explain":"<span class='basic_left'>G\u1ecdi $(d):\\,y=ax+b$. <br\/>\u0110\u01b0\u1eddng th\u1eb3ng $(d)$ vu\u00f4ng g\u00f3c v\u1edbi \u0111\u01b0\u1eddng th\u1eb3ng $y= x - 5$, ta c\u00f3: $a.1=-1\\Rightarrow a=-1$<br\/>Suy ra \u0111\u01b0\u1eddng th\u1eb3ng $(d)$ c\u00f3 d\u1ea1ng: $y=-x+b$<br\/>Do $A(4; -6)$ thu\u1ed9c \u0111\u01b0\u1eddng th\u1eb3ng $(d)$ n\u00ean ta c\u00f3: <br\/>$ -6=-4+ b \\Leftrightarrow b= -2$<br\/>V\u1eady \u0111\u01b0\u1eddng th\u1eb3ng c\u1ea7n t\u00ecm c\u00f3 ph\u01b0\u01a1ng tr\u00ecnh l\u00e0: $y = -x -2$. <br\/> <span class='basic_pink'>\u0110\u00e1p \u00e1n l\u00e0 D.<\/span> <\/span>","column":2}],"id_ques":206},{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["1"],["2"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","type_check":"","ques":"<span class='basic_left'>Cho hai \u0111\u01b0\u1eddng th\u1eb3ng : $y=2x$ v\u00e0 $y=-3x+5$. T\u00ecm t\u1ecda \u0111\u1ed9 giao \u0111i\u1ec3m $M$ c\u1ee7a hai \u0111\u01b0\u1eddng th\u1eb3ng $y=2x$ v\u00e0 $y=-3x+5$<br\/><b>\u0110\u00e1p \u00e1n:<\/b> T\u1ecda \u0111\u1ed9 c\u1ee7a \u0111i\u1ec3m $M$ l\u00e0 (_input_; _input_)<\/span>","hint":"X\u00e9t ph\u01b0\u01a1ng tr\u00ecnh ho\u00e0nh \u0111\u1ed9 giao \u0111i\u1ec3m.","explain":" <span class='basic_left'> Ta c\u00f3 $(d):\\,\\,y=2x\\,\\,$ v\u00e0 $(d'): \\,\\,y=-3x+5$<br\/> Theo b\u00e0i: $(d) \\cap (d') =M$. <br\/> Ho\u00e0nh \u0111\u1ed9 giao \u0111i\u1ec3m $M$ l\u00e0 nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh: <br\/>$2x=-3x+5\\Leftrightarrow x=1$<br\/>Tung \u0111\u1ed9 c\u1ee7a \u0111i\u1ec3m $M$ l\u00e0 $y= 2$.<br\/>V\u1eady t\u1ecda \u0111\u1ed9 c\u1ee7a \u0111i\u1ec3m $M$ l\u00e0 $(1; 2)$. <br\/><span class='basic_pink'>Do \u0111\u00f3 s\u1ed1 c\u1ea7n \u0111i\u1ec3n l\u00e0 $1;2$<\/span>"}],"id_ques":207},{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":10,"ques":"\u0110\u01b0\u1eddng th\u1eb3ng \u0111i qua hai \u0111i\u1ec3m $A (2; 5)$ v\u00e0 $B (1; -3)$ c\u00f3 ph\u01b0\u01a1ng tr\u00ecnh l\u00e0:","select":["A. $y=8x - 11$","B. $y=8x + 11$","C. $y=8x -5$ "],"hint":"Ph\u01b0\u01a1ng tr\u00ecnh \u0111\u01b0\u1eddng th\u1eb3ng $AB$ c\u00f3 d\u1ea1ng: $y = ax + b\\, (a\\ne 0)$<br\/>Thay t\u1ecda \u0111\u1ed9 \u0111i\u1ec3m $A$ v\u00e0 $B$ v\u00e0o \u0111\u01b0\u1eddng th\u1eb3ng \u0111\u1ec3 t\u00ecm $a;b$. ","explain":"<span class='basic_left'> Ph\u01b0\u01a1ng tr\u00ecnh \u0111\u01b0\u1eddng th\u1eb3ng $AB$ c\u00f3 d\u1ea1ng $y= ax + b\\, (a \\ne 0)$.<br\/>Do $A\\left( 2;5 \\right)\\,\\,\\in AB$ n\u00ean t\u1ecda \u0111\u1ed9 \u0111i\u1ec3m $A$ th\u1ecfa m\u00e3n ph\u01b0\u01a1ng tr\u00ecnh \u0111\u01b0\u1eddng th\u1eb3ng $AB$. <br\/> $\\Rightarrow 5=a.2+b\\,$$\\Leftrightarrow 2a+b=5\\,\\,\\,\\,(1) $<br\/>T\u01b0\u01a1ng t\u1ef1: $B\\left( 1;-3 \\right)\\in AB$$\\Rightarrow -3=a.1+b\\,$$\\Leftrightarrow b=-a-3\\,\\,\\,\\,(2) $<br\/>Thay (2) v\u00e0o (1) ta \u0111\u01b0\u1ee3c: $2a-a-3=5\\Leftrightarrow a=8 $<br\/> Thay $a=8$ v\u00e0o (2) \u0111\u01b0\u1ee3c: $b= -8-3=-11$ <br\/>Ph\u01b0\u01a1ng tr\u00ecnh \u0111\u01b0\u1eddng th\u1eb3ng $AB$ l\u00e0 : $y=8x-11$<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n l\u00e0 A.<\/span><\/span>","column":3}],"id_ques":208},{"title":"Ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"select":["A. $\\dfrac{60}{13}$","B. $\\dfrac{55}{13}$","C. $\\dfrac{53}{13}$"],"ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/daiso/bai13/lv3/img\/\/2.png' \/><\/center>Cho \u0111\u01b0\u1eddng th\u1eb3ng $(d):\\,\\,\\,y=-\\dfrac{12}{5}x+12$. <br\/>Kho\u1ea3ng c\u00e1ch t\u1eeb g\u1ed1c t\u1ecda \u0111\u1ed9 $O$ \u0111\u1ebfn \u0111\u01b0\u1eddng th\u1eb3ng $(d)$ l\u00e0 ?","hint":"D\u00f9ng h\u1ec7 th\u1ee9c gi\u1eefa \u0111\u01b0\u1eddng cao v\u00e0 c\u1ea1nh trong tam gi\u00e1c vu\u00f4ng $AOB$ ","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<br\/><\/span>B\u01b0\u1edbc 1:X\u00e1c \u0111\u1ecbnh giao \u0111i\u1ec3m c\u1ee7a \u0111\u1ed3 th\u1ecb v\u1edbi hai tr\u1ee5c t\u1ecda \u0111\u1ed9. <br\/>B\u01b0\u1edbc 2: D\u00f9ng h\u1ec7 th\u1ee9c gi\u1eefa c\u1ea1nh v\u00e0 \u0111\u01b0\u1eddng cao trong tam gi\u00e1c. <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/>Ta c\u00f3 $\\left( d \\right)\\cap \\text{Ox}=A(5;0);\\,\\,$$\\left( d \\right)\\cap Oy=B\\left( 0;12 \\right)$. H\u1ea1 $OH\\bot AB$ . <br\/><center><img src='https://www.luyenthi123.com/file/luyenthi123/lop9/toan/daiso/bai13/lv3/img\/\/D925_K1.png' \/><\/center><br\/> Theo h\u00ecnh v\u1ebd ta x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c: $OA=5;OB=12$. <br\/> \u00c1p d\u1ee5ng h\u1ec7 th\u1ee9c l\u01b0\u1ee3ng trong tam gi\u00e1c vu\u00f4ng $AOB$ ta c\u00f3: <br\/>$\\begin{aligned}\\dfrac{1}{O{{H}^{2}}}&=\\dfrac{1}{O{{A}^{2}}}+\\dfrac{1}{O{{B}^{2}}}\\\\&=\\dfrac{1}{{{5}^{2}}}+\\dfrac{1}{{{12}^{2}}}=\\dfrac{169}{3600}\\\\&\\Rightarrow OH=\\dfrac{60}{13}\\end{aligned}$ <br\/>Kho\u1ea3ng c\u00e1ch t\u1eeb O \u0111\u1ebfn \u0111\u01b0\u1eddng th\u1eb3ng $\\left( d \\right)$ l\u00e0 $\\dfrac{60}{13}$<br\/><span class='basic_green'>L\u01b0u \u00fd:<\/span> \u0110\u1ec3 gi\u1ea3i c\u00e1c b\u00e0i t\u1eadp d\u1ea1ng t\u00ecm kho\u1ea3ng c\u00e1ch t\u1eeb g\u1ed1c t\u1ecda \u0111\u1ed9 \u0111\u1ebfn \u0111\u01b0\u1eddng th\u1eb3ng, ta th\u01b0\u1eddng s\u1eed d\u1ee5ng h\u1ec7 th\u1ee9c l\u01b0\u1ee3ng trong tam gi\u00e1c vu\u00f4ng:<br\/>+ $\\dfrac{1}{O{{H}^{2}}}=\\dfrac{1}{O{{A}^{2}}}+\\dfrac{1}{O{{B}^{2}}}$<br\/>+ $OH.AB=OA.OB$ <span>"}],"id_ques":209},{"title":"H\u00e3y ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":10,"ques":"T\u00ecm t\u1eadp x\u00e1c \u0111\u1ecbnh c\u1ee7a h\u00e0m s\u1ed1 $y=\\sqrt{4-3x}+\\dfrac{1}{\\sqrt{x}}$ l\u00e0: ","select":["A. $x \\ge 0$ ","B. $x \\ge \\dfrac{4}{3}$","C. $x \\le \\dfrac{4}{3}$","D. $0 < x \\le \\dfrac{4}{3}$"],"hint":"Bi\u1ec3u th\u1ee9c x\u00e1c \u0111\u1ecbnh khi bi\u1ec3u th\u1ee9c trong c\u0103n kh\u00f4ng \u00e2m v\u00e0 m\u1eabu th\u1ee9c kh\u00e1c $0$. ","explain":"<span class='basic_left'> T\u1eadp x\u00e1c \u0111\u1ecbnh c\u1ee7a h\u00e0m s\u1ed1 $y=\\sqrt{4-3x}+\\dfrac{1}{\\sqrt{x}}$ l\u00e0: <br\/>$\\left\\{ \\begin{aligned} & 4-3x\\ge 0 \\\\ & x > 0 \\\\ \\end{aligned} \\right.\\,$$\\Leftrightarrow \\left\\{ \\begin{aligned} & x\\le \\dfrac{4}{3} \\\\ & x > 0 \\\\ \\end{aligned} \\right.\\,$$\\Leftrightarrow 0< x\\le \\dfrac{4}{3}$ <br\/> <span class='basic_pink'>\u0110\u00e1p \u00e1n l\u00e0 D.<\/span><\/span>","column":4}],"id_ques":210}],"id_ques":0}],"lesson":{"save":1,"level":3,"time":44}}

Điểm của bạn.

Câu hỏi này theo dạng chọn đáp án đúng, sau khi đọc xong câu hỏi, bạn bấm vào một trong số các đáp án mà chương trình đưa ra bên dưới, sau đó bấm vào nút gửi để kiểm tra đáp án và sẵn sàng chuyển sang câu hỏi kế tiếp

Trả lời đúng trong khoảng thời gian quy định bạn sẽ được + số điểm như sau:
Trong khoảng 1 phút đầu tiên + 5 điểm
Trong khoảng 1 phút -> 2 phút + 4 điểm
Trong khoảng 2 phút -> 3 phút + 3 điểm
Trong khoảng 3 phút -> 4 phút + 2 điểm
Trong khoảng 4 phút -> 5 phút + 1 điểm

Quá 5 phút: không được cộng điểm

Tổng thời gian làm mỗi câu (không giới hạn)

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Bấm vào đây nếu phát hiện có lỗi hoặc muốn gửi góp ý