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{"segment":[{"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":"<span class='basic_left'> Cho $x-y=1$. Gi\u00e1 tr\u1ecb c\u1ee7a \u0111a th\u1ee9c <br\/> $x^3-x^2y-x^2+xy^2-y^3-y^2+5x-5y-5-2012$ l\u00e0: <\/span>","select":["A. $-2011$","B. $-2012$","C. $-2013$ ","D. $-2014$"],"explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> Nh\u00f3m $3$ h\u1ea1ng t\u1eed li\u00ean ti\u1ebfp th\u00e0nh m\u1ed9t nh\u00f3m v\u00e0 \u0111\u1eb7t nh\u00e2n t\u1eed chung.<br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/>Ta c\u00f3: <br\/> $\\begin{align} & Q={{x}^{3}}-{{x}^{2}}y-{{x}^{2}}+x{{y}^{2}}-{{y}^{3}}-{{y}^{2}}+5x-5y-5-2012 \\\\ & \\,\\,\\,\\,\\,=\\left( {{x}^{3}}-{{x}^{2}}y-{{x}^{2}} \\right)+\\left( x{{y}^{2}}-{{y}^{3}}-{{y}^{2}} \\right)+\\left( 5x-5y-5 \\right)-2012 \\\\ & \\,\\,\\,\\,\\,={{x}^{2}}\\left( x-y-1 \\right)+{{y}^{2}}\\left( x-y-1 \\right)+5\\left( x-y-1 \\right)-2012 \\\\ & \\,\\,\\,\\,\\,={{x}^{2}}\\left( 1-1 \\right)+{{y}^{2}}\\left( 1-1 \\right)+5\\left( 1-1 \\right)-2012 \\\\ & \\,\\,\\,\\,\\,=-2012 \\\\ \\end{align}$ <br\/><span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 B.<\/span> <\/span>","column":4}]}],"id_ques":1191},{"time":24,"part":[{"title":"Kh\u1eb3ng \u0111\u1ecbnh sau \u0111\u00e2y \u0110\u00fang hay Sai","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":10,"ques":" <span class='basic_left'> Cho c\u00e1c \u0111a th\u1ee9c sau: <br\/> $P=5{{x}^{2}}{{y}^{2}}-xy-2{{y}^{3}}-{{y}^{2}}+5{{x}^{4}} $ <br\/> $Q= -2{{x}^{2}}{{y}^{2}}-5xy+{{y}^{3}}-3{{y}^{2}}+2{{x}^{4}} $ <br\/> $N= -{{x}^{2}}{{y}^{2}}+6xy+{{y}^{3}}+6{{y}^{2}}+7$ <br\/> V\u1edbi m\u1ecdi $x;y$ th\u00ec \u00edt nh\u1ea5t m\u1ed9t trong ba \u0111a th\u1ee9c tr\u00ean c\u00f3 gi\u00e1 tr\u1ecb d\u01b0\u01a1ng. <\/span>","select":["\u0110\u00fang","Sai "],"hint":"So s\u00e1nh t\u1ed5ng $P+Q+N$ v\u1edbi $0$","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/>X\u00e9t t\u1ed5ng ba \u0111a th\u1ee9c \u0111\u00e3 cho v\u00e0 so s\u00e1nh t\u1ed5ng \u0111\u00f3 v\u1edbi $0$ <br\/> N\u1ebfu $P+Q+N > 0$ th\u00ec kh\u1eb3ng \u0111\u1ecbnh tr\u00ean l\u00e0 \u0111\u00fang. <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> X\u00e9t t\u1ed5ng ba \u0111a th\u1ee9c \u0111\u00e3 cho: <br\/> $\\begin{aligned} & P+Q+N \\\\ & =\\left( 5{{x}^{2}}{{y}^{2}}-xy-2{{y}^{3}}-{{y}^{2}}+5{{x}^{4}} \\right)+\\left( -2{{x}^{2}}{{y}^{2}}-5xy+{{y}^{3}}-3{{y}^{2}}+2{{x}^{4}} \\right)+\\left( -{{x}^{2}}{{y}^{2}}+6xy+{{y}^{3}}+6{{y}^{2}}+7 \\right) \\\\ & =5{{x}^{2}}{{y}^{2}}-xy-2{{y}^{3}}-{{y}^{2}}+5{{x}^{4}}-2{{x}^{2}}{{y}^{2}}-5xy+{{y}^{3}}-3{{y}^{2}}+2{{x}^{4}}-{{x}^{2}}{{y}^{2}}+6xy+{{y}^{3}}+6{{y}^{2}}+7 \\\\ & =\\left( 5{{x}^{2}}{{y}^{2}}-2{{x}^{2}}{{y}^{2}}-{{x}^{2}}{{y}^{2}} \\right)+\\left( -xy-5xy+6xy \\right)+\\left( -2{{y}^{3}}+{{y}^{3}}+{{y}^{3}} \\right)+\\left( -{{y}^{2}}-3{{y}^{2}}+6{{y}^{2}} \\right)+\\left( 5{{x}^{4}}+2{{x}^{4}} \\right)+7 \\\\ & =2{{x}^{2}}{{y}^{2}}+2{{y}^{2}}+7{{x}^{4}}+7 \\\\ & Do\\,\\,\\left\\{ \\begin{aligned} & 2{{x}^{2}}{{y}^{2}}\\ge 0 \\\\ & 2{{y}^{2}}\\ge 0 \\\\ & 7{{x}^{4}}\\ge 0 \\\\ \\end{aligned} \\right.\\Rightarrow 2{{x}^{2}}{{y}^{2}}+2{{y}^{2}}+7{{x}^{4}}+7>0\\,\\,\\,\\,\\forall x;y \\\\ & \\, \\\\ \\end{aligned}$ <br\/> $\\Rightarrow$ V\u1edbi m\u1ecdi $x;y$ th\u00ec \u00edt nh\u1ea5t m\u1ed9t trong ba \u0111a th\u1ee9c tr\u00ean c\u00f3 gi\u00e1 tr\u1ecb d\u01b0\u01a1ng. <br\/><span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 \u0110\u00fang.<\/span><\/span>","column":2}]}],"id_ques":1192},{"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":"<span class='basic_left'> Cho hai \u0111a th\u1ee9c sau: <br\/> $P=\\left[ \\dfrac{1}{2}a\\,x-2\\left( a\\,x+3 \\right) \\right]-\\left( a\\,x+1 \\right)$ <br\/> $Q=a\\,x-2-\\left[ 3-\\left( a\\,x-1 \\right) \\right]-4$ <br\/> T\u1ed5ng $P+Q$ l\u00e0: <\/span>","select":["A. $\\dfrac{3}{2}a\\,x+16$","B. $-\\dfrac{3}{2}a\\,x-16$","C. $\\dfrac{1}{2}a\\,x+17$ ","D. $-\\dfrac{1}{2}a\\,x-17$"],"explain":"<span class='basic_left'>Ta c\u00f3: <br\/> $\\begin{align} & P+Q \\\\ & =\\left[ \\dfrac{1}{2}a\\,x-2\\left( a\\,x+3 \\right) \\right]-\\left( a\\,x+1 \\right)+a\\,x-2-\\left[ 3-\\left( a\\,x-1 \\right) \\right]-4 \\\\ & =\\dfrac{1}{2}a\\,x-2a\\,x-6-a\\,x-1+a\\,x-2-3+a\\,x-1-4 \\\\ & =\\left( \\dfrac{1}{2}a\\,x-2a\\,x-a\\,x+a\\,x+a\\,x \\right)+\\left( -6-1-2-3-1-4 \\right) \\\\ & =-\\dfrac{1}{2}a\\,x-17 \\\\ \\end{align}$ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 D.<\/span> <\/span>","column":2}]}],"id_ques":1193},{"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":"<span class='basic_left'> T\u1ed5ng c\u1ee7a \u0111a th\u1ee9c $A$ v\u1edbi \u0111a th\u1ee9c $2x^4-3x^2y+y^4+3xz+z^2$ l\u00e0 m\u1ed9t \u0111a th\u1ee9c kh\u00f4ng ch\u1ee9a bi\u1ebfn $x.$ <br\/> \u0110a th\u1ee9c $A$ th\u1ecfa m\u00e3n \u0111\u1ec1 b\u00e0i l\u00e0: <\/span>","select":["A. $-2x^4+3x^2y-3xz$","B. $2x^4+3x^2y-3xz+1$","C. $x^4+x^2y-xz$ ","D. $-x^4-x^2y+xz+1$"],"explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> \u0110\u1ec3 t\u1ed5ng c\u1ee7a $A$ v\u00e0 \u0111a th\u1ee9c \u0111\u00e3 cho l\u00e0 m\u1ed9t \u0111a th\u1ee9c kh\u00f4ng ch\u1ee9a bi\u1ebfn $x$ th\u00ec \u0111a th\u1ee9c $A$ c\u00f3 nhi\u1ec1u \u0111\u00e1p \u00e1n th\u1ecfa m\u00e3n. <br\/> Do \u0111\u00f3 ta th\u1eed \u0111a th\u1ee9c $A$ \u1edf c\u00e1c \u0111\u00e1p \u00e1n xem \u0111\u00e1p \u00e1n n\u00e0o th\u1ecfa m\u00e3n.<br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> Ta c\u00f3: <br\/> $\\begin{align} & \\left( -2{{x}^{4}}+3{{x}^{2}}y-3xz \\right)+\\left( 2{{x}^{4}}-3{{x}^{2}}y+{{y}^{4}}+3xz+{{z}^{2}} \\right) \\\\ & =\\left( -2{{x}^{4}}+2{{x}^{4}} \\right)+\\left( 3{{x}^{2}}y-3{{x}^{2}}y \\right)+\\left( -3xz+3xz \\right)+{{y}^{4}}+{{z}^{2}} \\\\ & ={{y}^{4}}+{{z}^{2}}\\,\\, \\\\ \\end{align}$ <br\/> $\\Rightarrow$ \u0110\u00e1p \u00e1n A th\u1ecfa m\u00e3n. <br\/> $\\begin{align} & \\left( 2{{x}^{4}}+3{{x}^{2}}y-3xz+1 \\right)+\\left( 2{{x}^{4}}-3{{x}^{2}}y+{{y}^{4}}+3xz+{{z}^{2}} \\right) \\\\ & =\\left( 2{{x}^{4}}+2{{x}^{4}} \\right)+\\left( 3{{x}^{2}}y-3{{x}^{2}}y \\right)+\\left( -3xz+3xz \\right)+1+{{y}^{4}}+{{z}^{2}} \\\\ & =4{{x}^{4}}+1+{{y}^{4}}+{{z}^{2}}\\,\\, \\\\ \\end{align}$ <br\/> $\\Rightarrow$ \u0110\u00e1p \u00e1n B kh\u00f4ng th\u1ecfa m\u00e3n. <br\/> $\\begin{align} & \\left( {{x}^{4}}+{{x}^{2}}y-xz \\right)+\\left( 2{{x}^{4}}-3{{x}^{2}}y+{{y}^{4}}+3xz+{{z}^{2}} \\right) \\\\ & =\\left( {{x}^{4}}+2{{x}^{4}} \\right)+\\left( {{x}^{2}}y-3{{x}^{2}}y \\right)+\\left( -xz+3xz \\right)+{{y}^{4}}+{{z}^{2}} \\\\ & =3{{x}^{4}}-2{{x}^{2}}y+2xz+{{y}^{4}}+{{z}^{2}}\\,\\, \\\\ \\end{align}$ <br\/>$\\Rightarrow$ \u0110\u00e1p \u00e1n C kh\u00f4ng th\u1ecfa m\u00e3n. <br\/> $\\begin{align}& \\left( -{{x}^{4}}-{{x}^{2}}y+xz+1 \\right)+\\left( 2{{x}^{4}}-3{{x}^{2}}y+{{y}^{4}}+3xz+{{z}^{2}} \\right) \\\\ & =\\left( -{{x}^{4}}+2{{x}^{4}} \\right)+\\left( -{{x}^{2}}y-3{{x}^{2}}y \\right)+\\left( xz+3xz \\right)+1+{{y}^{4}}+{{z}^{2}} \\\\ & ={{x}^{4}}-4{{x}^{2}}y+4xz+1+{{y}^{4}}+{{z}^{2}}\\,\\, \\\\ \\end{align}$ <br\/> $\\Rightarrow $ \u0110\u00e1p \u00e1n D kh\u00f4ng th\u1ecfa m\u00e3n. <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 A.<\/span> <\/span>","column":2}]}],"id_ques":1194},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 \u0111\u00fang nh\u1ea5t v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["1"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","ques":" <span class='basic_left'> Bi\u1ebft $x+y-2=0.$ <br\/> Gi\u00e1 tr\u1ecb c\u1ee7a \u0111a th\u1ee9c $M=x^3+x^2y-2x^2-xy-y^2+3y+x-1$ l\u00e0 _input_ <\/span>","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> Bi\u1ebfn \u0111\u1ed5i $M$ l\u00e0m xu\u1ea5t hi\u1ec7n th\u1eeba s\u1ed1 $x+y-2$ <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> Ta c\u00f3: <br\/> $\\begin{align} & M={{x}^{3}}+{{x}^{2}}y-2{{x}^{2}}-xy-{{y}^{2}}+3y+x-1 \\\\ & \\,\\,\\,\\,\\,\\,=\\left( {{x}^{3}}+{{x}^{2}}y-2{{x}^{2}} \\right)+\\left( -xy-{{y}^{2}}+2y \\right)+\\left( x+y-2 \\right)+1 \\\\ & \\,\\,\\,\\,\\,\\,={{x}^{2}}\\left( x+y-2 \\right)-y\\left( x+y-2 \\right)+\\left( x+y-2 \\right)+1 \\\\ & \\,\\,\\,\\,\\,={{x}^{2}}.0-y.0+0+1 \\\\ & \\,\\,\\,\\,\\,=1 \\\\ \\end{align}$ <br\/> <span class='basic_pink'> V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $1$ <\/span><\/span>"}]}],"id_ques":1195},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 \u0111\u00fang nh\u1ea5t v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["3"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","ques":" <span class='basic_left'> T\u00ecm $x,$ bi\u1ebft $|x-2|=|4-x|$ <br\/> <b> \u0110\u00e1p \u00e1n:<\/b> $x=\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}$ <\/span>","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> $|A|=|B| \\Rightarrow \\left[ \\begin{align} & A=B \\\\ & A=-B \\\\ \\end{align} \\right.$ <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> Ta c\u00f3: <br\/> $\\begin{aligned} & |x-2|=|4-x| \\\\ & \\Rightarrow \\left[ \\begin{aligned} & x-2=4-x \\\\ & x-2=x-4 \\\\ \\end{aligned} \\right. \\\\ & \\Rightarrow \\left[ \\begin{aligned} & 2x=6 \\\\ & 0=-2\\,\\text{(v\u00f4 l\u00ed)} \\\\ \\end{aligned} \\right. \\\\ & \\Rightarrow x=3 \\\\ \\end{aligned}$ <br\/> <span class='basic_pink'> V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $3$ <\/span><\/span>"}]}],"id_ques":1196},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"\u0110\u1ec1 chung cho hai c\u00e2u","temp":"multiple_choice","correct":[[3]],"list":[{"point":10,"ques":"<span class='basic_left'> Cho bi\u1ebft $M+\\left( 3{{x}^{3}}+3{{x}^{2}}y-3x{{y}^{2}}+xy-{{x}^{2}}-1 \\right)=\\left( 3{{x}^{3}}+3{{x}^{2}}y-3x{{y}^{2}}+xy \\right)$ <br\/> <b> C\u00e2u 1:<\/b> \u0110a th\u1ee9c $M$ l\u00e0: <\/span>","select":["A. $2xy+x+1$","B. $6x^2y+6xy^2+x^2+1$","C. $x^2+1$ ","D. $1$"],"explain":"<span class='basic_left'> Ta c\u00f3: <br\/> $\\begin{align} & M+\\left( 3{{x}^{3}}+3{{x}^{2}}y-3x{{y}^{2}}+xy-{{x}^{2}}-1 \\right)=\\left( 3{{x}^{3}}+3{{x}^{2}}y-3x{{y}^{2}}+xy \\right) \\\\ & M=\\left( 3{{x}^{3}}+3{{x}^{2}}y-3x{{y}^{2}}+xy \\right)-\\left( 3{{x}^{3}}+3{{x}^{2}}y-3x{{y}^{2}}+xy-{{x}^{2}}-1 \\right) \\\\ & \\,\\,\\,\\,\\,\\,\\,=3{{x}^{3}}+3{{x}^{2}}y-3x{{y}^{2}}+xy-3{{x}^{3}}-3{{x}^{2}}y+3x{{y}^{2}}-xy+{{x}^{2}}+1 \\\\ & \\,\\,\\,\\,\\,\\,\\,=\\left( 3{{x}^{3}}-3{{x}^{3}} \\right)+\\left( 3{{x}^{2}}y-3{{x}^{2}}y \\right)+\\left( -3x{{y}^{2}}+3x{{y}^{2}} \\right)+\\left( xy-xy \\right)+{{x}^{2}}+1 \\\\ & \\,\\,\\,\\,\\,\\,\\,=0+0+0+0+{{x}^{2}}+1 \\\\ & \\,\\,\\,\\,\\,\\,\\,={{x}^{2}}+1 \\\\ \\end{align}$ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 C.<\/span> <\/span>","column":2}]}],"id_ques":1197},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 \u0111\u00fang nh\u1ea5t v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"\u0110\u1ec1 chung cho hai c\u00e2u","temp":"fill_the_blank_random","correct":[[["4"],["-4"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","ques":" <span class='basic_left'> Cho bi\u1ebft $M+\\left( 3{{x}^{3}}+3{{x}^{2}}y-3x{{y}^{2}}+xy-{{x}^{2}}-1 \\right)=\\left( 3{{x}^{3}}+3{{x}^{2}}y-3x{{y}^{2}}+xy \\right)$ <br\/> <b> C\u00e2u 2:<\/b> T\u00ecm gi\u00e1 tr\u1ecb c\u1ee7a $x$ \u0111\u1ec3 $M=17$ <br\/> <b> \u0110\u00e1p \u00e1n:<\/b> $\\left[ \\begin{align} & x=\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} \\\\ & x=\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} \\\\ \\end{align} \\right.$ <\/span>","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> Cho \u0111a th\u1ee9c $M$ b\u1eb1ng $17$ v\u00e0 t\u00ecm $x$ <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> Theo c\u00e2u 1, ta t\u00ecm \u0111\u01b0\u1ee3c $M=x^2+1$ <br\/> Ta c\u00f3: <br\/> $x^2+1=17$ <br\/> $x^2=17-1$ <br\/> $x^2=16$ <br\/> $\\Rightarrow \\left[ \\begin{align} & x=4 \\\\ & x=-4 \\\\ \\end{align} \\right.$ <br\/> <span class='basic_pink'> V\u1eady c\u00e1c s\u1ed1 c\u1ea7n \u0111i\u1ec1n v\u00e0o c\u00e1c \u00f4 tr\u1ed1ng l\u00e0 $4$ v\u00e0 $-4$ <\/span><\/span>"}]}],"id_ques":1198},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 \u0111\u00fang nh\u1ea5t v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["1"],["1"],["1"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","ques":" <span class='basic_left'> T\u00ecm gi\u00e1 tr\u1ecb c\u1ee7a $x;y;z$ th\u1ecfa m\u00e3n $(1-x)^2+(x-y)^2+(y-z)^2=0$ <br\/> <b> \u0110\u00e1p \u00e1n:<\/b> $\\left\\{ \\begin{align} & x=\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} \\\\ & y=\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} \\\\ & z=\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} \\\\ \\end{align} \\right. $ <\/span>","explain":"<span class='basic_left'> $\\begin{aligned} & Do\\,\\,{{\\left( 1-x \\right)}^{2}}\\ge 0;\\,\\,{{\\left( x-y \\right)}^{2}}\\,\\,\\ge 0;\\,\\,{{\\left( y-z \\right)}^{2}}\\,\\ge 0 \\,\\forall\\,x,y,z \\\\ & \u0110\u1ec3\\,\\,{{(1-x)}^{2}}+{{(x-y)}^{2}}+{{(y-z)}^{2}}=0 \\\\ & \\Rightarrow \\left\\{ \\begin{aligned} & 1-x=0 \\\\ & x-y=0 \\\\ & y-z=0 \\\\ \\end{aligned} \\right.\\Rightarrow \\left\\{ \\begin{aligned} & x=1 \\\\ & y=x=1 \\\\ & z=y=1 \\\\ \\end{aligned} \\right. \\\\ \\end{aligned}$ <br\/> <span class='basic_pink'> V\u1eady c\u00e1c s\u1ed1 c\u1ea7n \u0111i\u1ec1n v\u00e0o c\u00e1c \u00f4 tr\u1ed1ng l\u1ea7n l\u01b0\u1ee3t l\u00e0 $1;1$ v\u00e0 $1$ <\/span><\/span>"}]}],"id_ques":1199},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 \u0111\u00fang nh\u1ea5t v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["6"],["0"],["0"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","ques":" <span class='basic_left'> T\u00ecm gi\u00e1 tr\u1ecb l\u1edbn nh\u1ea5t c\u1ee7a bi\u1ec3u th\u1ee9c: <br\/> $M=\\left( {{x}^{2}}{{y}^{3}}+{{x}^{3}}{{y}^{2}}-{{x}^{2}}+{{y}^{2}}+5 \\right)-\\left( {{x}^{2}}{{y}^{3}}+{{x}^{3}}{{y}^{2}}+2{{y}^{2}}-1 \\right)$ <br\/> <b> \u0110\u00e1p \u00e1n:<\/b> Gi\u00e1 tr\u1ecb l\u1edbn nh\u1ea5t c\u1ee7a $M$ l\u00e0 _input_ khi $\\left\\{ \\begin{align} & x=\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} \\\\ & y=\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} \\\\ \\end{align} \\right. $ <\/span>","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> Thu g\u1ecdn bi\u1ec3u th\u1ee9c $M$ <br\/> Nh\u1eadn \u0111\u1ecbnh, \u0111\u00e1nh gi\u00e1 \u0111\u1ec3 t\u00ecm $Max\\,M$ <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> $\\begin{aligned} & M=\\left( {{x}^{2}}{{y}^{3}}+{{x}^{3}}{{y}^{2}}-{{x}^{2}}+{{y}^{2}}+5 \\right)-\\left( {{x}^{2}}{{y}^{3}}+{{x}^{3}}{{y}^{2}}+2{{y}^{2}}-1 \\right) \\\\ & \\,\\,\\,\\,\\,\\,\\,={{x}^{2}}{{y}^{3}}+{{x}^{3}}{{y}^{2}}-{{x}^{2}}+{{y}^{2}}+5-{{x}^{2}}{{y}^{3}}-{{x}^{3}}{{y}^{2}}-2{{y}^{2}}+1 \\\\ & \\,\\,\\,\\,\\,\\,\\,=\\left( {{x}^{2}}{{y}^{3}}-{{x}^{2}}{{y}^{3}} \\right)+\\left( {{x}^{3}}{{y}^{2}}-{{x}^{3}}{{y}^{2}} \\right)-{{x}^{2}}+\\left( {{y}^{2}}-2{{y}^{2}} \\right)+5+1 \\\\ & \\,\\,\\,\\,\\,\\,\\,=0+0-{{x}^{2}}-{{y}^{2}}+6 \\\\ & \\,\\,\\,\\,\\,\\,\\,=-{{x}^{2}}-{{y}^{2}}+6 \\\\ & Do\\,\\,\\left\\{ \\begin{aligned} & {{x}^{2}}\\,\\,\\ge 0\\,\\forall\\,x \\\\ & {{y}^{2}}\\ge 0\\,\\forall\\,y \\\\ \\end{aligned} \\right.\\Rightarrow \\left\\{ \\begin{aligned} & -{{x}^{2}}\\le 0 \\,\\forall\\,x \\\\ & -{{y}^{2}}\\le 0 \\,\\forall \\,y \\\\ \\end{aligned} \\right. \\\\ & \\Rightarrow M=-{{x}^{2}}-{{y}^{2}}+6\\le 6 \\,\\forall\\,x,y \\\\ & \\Rightarrow Ma{{x}{M}}=6\\,\\,khi\\,\\,x=y=0 \\\\ \\end{aligned}$ <br\/> <span class='basic_pink'> V\u1eady c\u00e1c s\u1ed1 c\u1ea7n \u0111i\u1ec1n v\u00e0o c\u00e1c \u00f4 tr\u1ed1ng l\u1ea7n l\u01b0\u1ee3t l\u00e0 $6;0$ v\u00e0 $0$ <\/span><\/span>"}]}],"id_ques":1200}],"lesson":{"save":0,"level":3}}

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)

Điểm của bạn.

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