{"segment":[{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t ","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":" <span class='basic_left'> Ph\u01b0\u01a1ng tr\u00ecnh n\u00e0o sau \u0111\u00e2y l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh m\u1ed9t \u1ea9n?<\/span>","select":["A. $\\dfrac{1}{4}x^2-3=0$","B. $\\dfrac{1}{2}-3x=5x-2y$","C. $x^2-y=0$","D. $2x+3y=0$"],"explain":" <span class='basic_left'> A. Ph\u01b0\u01a1ng tr\u00ecnh $\\dfrac{1}{4}x^2-3=0$ l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh m\u1ed9t \u1ea9n <br\/> B. Ph\u01b0\u01a1ng tr\u00ecnh $\\dfrac{1}{2}-3x=5x-2y$ l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t v\u1edbi hai \u1ea9n $x, y$ <br\/> C. Ph\u01b0\u01a1ng tr\u00ecnh $x^2-y=0$ l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc hai v\u1edbi hai \u1ea9n $x, y$ <br\/> D. $2x + 3y = 0$ l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t v\u1edbi hai \u1ea9n $x, y$<br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 A <\/span> <br\/> <b> L\u01b0u \u00fd: <\/b> <i> M\u1ed9t ph\u01b0\u01a1ng tr\u00ecnh v\u1edbi \u1ea9n $x$ c\u00f3 d\u1ea1ng $A(x)=B(x)$, trong \u0111\u00f3 v\u1ebf tr\u00e1i v\u00e0 v\u1ebf ph\u1ea3i l\u00e0 c\u00e1c bi\u1ec3u th\u1ee9c c\u00f9ng m\u1ed9t bi\u1ebfn $x$. <\/i> <\/span> ","column":2}]}],"id_ques":811},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t ","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":" <span class='basic_left'> Ph\u01b0\u01a1ng tr\u00ecnh n\u00e0o sau \u0111\u00e2y <b>kh\u00f4ng ph\u1ea3i<\/b> ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n? <\/span>","select":["A. $1-2y=y$","B. $(7+y)^2=y$","C. $1-3x=5x+2$","D. $x=0$"],"explain":" <span class='basic_left'>A. Ph\u01b0\u01a1ng trinh $1 - 2y = y$ l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n $y$ <br\/> B. Ph\u01b0\u01a1ng tr\u00ecnh $(7+y)^2=y$ kh\u00f4ng ph\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n v\u00ec \u1ea9n $y$ c\u00f3 b\u1eadc cao nh\u1ea5t l\u00e0 $2$. <br\/> C. Ph\u01b0\u01a1ng tr\u00ecnh $1 - 3x = 5x + 2$ l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n v\u1edbi \u1ea9n $x$. <br\/> D. Ph\u01b0\u01a1ng tr\u00ecnh $x = 0$ l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n v\u1edbi \u1ea9n $x$. <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 B <\/span> <br\/> <b> L\u01b0u \u00fd: <\/b> <i> Ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n c\u00f3 d\u1ea1ng: $ax+b=0\\,\\,(a\\ne 0)$ <\/i> <\/span> ","column":2}]}],"id_ques":812},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t ","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":" <span class='basic_left'> Ph\u01b0\u01a1ng tr\u00ecnh $(3-5x)+(6x-10)-9=0$ c\u00f3 nghi\u1ec7m l\u00e0: <\/span>","select":["A. $x=16$","B. $x=15$","C. $x=14$","D. $x=13$ "],"explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b> \u0110\u01b0a ph\u01b0\u01a1ng tr\u00ecnh $(3-5x)+(6x-10)-9=0$ v\u1ec1 d\u1ea1ng ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n <br\/> <b> B\u01b0\u1edbc 2: <\/b> \u00c1p d\u1ee5ng quy t\u1eafc chuy\u1ec3n v\u1ebf v\u00e0 quy t\u1eafc nh\u00e2n \u0111\u1ec3 t\u00ecm nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i<\/span> <br\/> Ta c\u00f3: <br\/> $(3-5x)+(6x-10)-9=0$ <br\/> $\\Leftrightarrow 3-5x+6x-10-9=0$ <br\/> $\\Leftrightarrow x-16=0$ <br\/> $\\Leftrightarrow x=16$ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 A <\/span> <\/span> ","column":4}]}],"id_ques":813},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t ","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":" <span class='basic_left'> Ph\u01b0\u01a1ng tr\u00ecnh $1,2-(x-0,8)=-2(0,9+x)$ c\u00f3 nghi\u1ec7m l\u00e0: <\/span>","select":["A. $x=-3$","B. $x=-4$","C. $x=-3,8$","D. $x=-4,2$ "],"explain":" <span class='basic_left'> Ta c\u00f3: <br\/> $1,2-(x-0,8)=-2(0,9+x)$ <br\/> $\\Leftrightarrow 1,2-x+0,8=-1,8-2x$ <br\/> $\\Leftrightarrow -x+2x=-1,8-1,2-0,8$ <br\/> $\\Leftrightarrow x=-3,8$ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 C <\/span> <\/span> ","column":4}]}],"id_ques":814},{"time":24,"part":[{"title":"Kh\u1eb3ng \u0111\u1ecbnh sau \u0111\u00e2y <b> \u0110\u00fang<\/b> hay <b> Sai<\/b> ","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":" <span class='basic_left'> C\u1eb7p ph\u01b0\u01a1ng tr\u00ecnh $\\dfrac{1}{5}x=0$ v\u00e0 $\\dfrac{1}{5}x=x$ t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi nhau. <\/span>","select":[" \u0110\u00fang"," Sai "],"explain":" <span class='basic_left'> X\u00e9t $\\dfrac{1}{5}x=0$ <br\/> $\\Leftrightarrow x=0$ <br\/> T\u1eadp nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh $\\dfrac{1}{5}x=0$ l\u00e0: $S = \\{0\\}$ <br\/> X\u00e9t ph\u01b0\u01a1ng tr\u00ecnh c\u00f2n l\u1ea1i: <br\/> $\\dfrac{1}{5}x=x$ <br\/> $\\Leftrightarrow \\dfrac{1}{5}x-x=0$ <br\/> $\\Leftrightarrow -\\dfrac{4}{5}x=0$ <br\/> $\\Leftrightarrow x=0$ <br\/> T\u1eadp nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh $\\dfrac{1}{5}x=x$ l\u00e0: $S = \\{0\\}$ <br\/> Do \u0111\u00f3, hai ph\u01b0\u01a1ng tr\u00ecnh $\\dfrac{1}{5}x=0$ v\u00e0 $\\dfrac{1}{5}x=x$ t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi nhau <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 \u0110\u00fang <\/span> <br\/> <b> L\u01b0u \u00fd: <\/b> <i> \u0110\u1ec3 ch\u1ee9ng t\u1ecf hai ph\u01b0\u01a1ng tr\u00ecnh (1) v\u00e0 (2) t\u01b0\u01a1ng \u0111\u01b0\u01a1ng c\u00f3 hai c\u00e1ch hay d\u00f9ng: <br\/> <b> C\u00e1ch 1: <\/b> Ch\u1ee9ng t\u1ecf (1) v\u00e0 (2) c\u00f3 c\u00e1c t\u1eadp nghi\u1ec7m $S_1$ v\u00e0 $S_2$ b\u1eb1ng nhau. <br\/> <b> C\u00e1ch 2: <\/b> D\u00f9ng ph\u00e9p bi\u1ebfn \u0111\u1ed5i t\u01b0\u01a1ng \u0111\u01b0\u01a1ng \u0111\u1ec3 bi\u1ebfn (1) th\u00e0nh (2) ho\u1eb7c bi\u1ebfn \u0111\u1ed5i (2) th\u00e0nh (1). <\/i> <\/span> ","column":2}]}],"id_ques":815},{"time":24,"part":[{"title":"Kh\u1eb3ng \u0111\u1ecbnh sau \u0111\u00e2y <b> \u0110\u00fang<\/b> hay <b> Sai<\/b> ","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":" <span class='basic_left'> C\u1eb7p ph\u01b0\u01a1ng tr\u00ecnh $x+1=x$ v\u00e0 $x^2+1=0$ t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi nhau. <\/span>","select":[" \u0110\u00fang"," Sai "],"explain":" <span class='basic_left'> X\u00e9t $x+1=x$ <br\/> $\\Leftrightarrow x-x=-1$ <br\/> $\\Leftrightarrow 0x=-1$ (kh\u00f4ng c\u00f3 gi\u00e1 tr\u1ecb n\u00e0o c\u1ee7a $x$ th\u1ecfa m\u00e3n) <br\/> T\u1eadp nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh $x+1=x$ l\u00e0: $S = \\varnothing$ <br\/> X\u00e9t ph\u01b0\u01a1ng tr\u00ecnh c\u00f2n l\u1ea1i: <br\/> $x^2+1=0$ <br\/> Nh\u1eadn th\u1ea5y: $x^2\\ge 0 \\hspace{0,2cm} \\forall x$ $\\Rightarrow x^2+1\\ge 1 > 0 \\,\\,\\forall x$ <br\/> T\u1eadp nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh $x^2+1=0$ l\u00e0: $S = \\varnothing$ <br\/> Do \u0111\u00f3, hai ph\u01b0\u01a1ng tr\u00ecnh $x+1=x$ v\u00e0 $x^2+1=0$ t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi nhau <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 \u0110\u00fang <\/span> <br\/> <b> L\u01b0u \u00fd: <\/b> <i> \u0110\u1ec3 ch\u1ee9ng t\u1ecf hai ph\u01b0\u01a1ng tr\u00ecnh (1) v\u00e0 (2) t\u01b0\u01a1ng \u0111\u01b0\u01a1ng c\u00f3 hai c\u00e1ch hay d\u00f9ng: <br\/> <b> C\u00e1ch 1: <\/b> Ch\u1ee9ng t\u1ecf (1) v\u00e0 (2) c\u00f3 c\u00e1c t\u1eadp nghi\u1ec7m $S_1$ v\u00e0 $S_2$ b\u1eb1ng nhau. <br\/> <b> C\u00e1ch 2: <\/b> D\u00f9ng ph\u00e9p bi\u1ebfn \u0111\u1ed5i t\u01b0\u01a1ng \u0111\u01b0\u01a1ng \u0111\u1ec3 bi\u1ebfn (1) th\u00e0nh (2) ho\u1eb7c bi\u1ebfn \u0111\u1ed5i (2) th\u00e0nh (1). <\/i> <\/span> ","column":2}]}],"id_ques":816},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["4"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<span class='basic_left'> Cho $2x-2=0$. Gi\u00e1 tr\u1ecb c\u1ee7a $5x^2-1$ l\u00e0 $\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}$ <\/span> ","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn<\/span><br\/> <b> B\u01b0\u1edbc 1: <\/b> Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh $2x-2=0$ \u0111\u1ec3 t\u00ecm $x$ <br\/> <b> B\u01b0\u1edbc 2: <\/b> Thay $x$ v\u1eeba t\u00ecm \u0111\u01b0\u1ee3c th\u1ebf v\u00e0o $5x^2-1$ <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i<\/span> <br\/> Ta c\u00f3: <br\/> $\\begin{align} & 2x-2=0 \\\\ & \\Leftrightarrow 2x=2 \\\\ & \\Leftrightarrow x=1 \\\\ \\end{align}$ <br\/> Thay $x=1$ v\u00e0o bi\u1ec3u th\u1ee9c $5x^2-1$, ta \u0111\u01b0\u1ee3c: <br\/> $5x^2-1=5.1^2-1=4$ <br\/> <span class='basic_pink'> V\u1eady c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $4$ <\/span> <\/span> "}]}],"id_ques":817},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["33"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<span class='basic_left'> Cho $4x-1=-3x+13$. Gi\u00e1 tr\u1ecb c\u1ee7a $49-2x^3$ l\u00e0 $\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}$ <\/span> ","explain":" <span class='basic_left'> Ta c\u00f3: <br\/> $\\begin{align} & 4x-1=-3x+13 \\\\ & \\Leftrightarrow 4x+3x=13+1 \\\\ & \\Leftrightarrow 7x=14 \\\\ & \\Leftrightarrow x=2 \\\\ \\end{align}$ <br\/> Thay $x=2$ v\u00e0o ph\u01b0\u01a1ng tr\u00ecnh $49-2x^3$, ta \u0111\u01b0\u1ee3c: <br\/> $49-2x^3=49-2.2^3=33$ <br\/> <span class='basic_pink'> V\u1eady c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $33$ <\/span> <\/span> "}]}],"id_ques":818},{"time":24,"part":[{"time":3,"title":"S\u1eafp x\u1ebfp c\u00e1c c\u00e2u \u0111\u1ec3 \u0111\u01b0\u1ee3c m\u1ed9t b\u00e0i gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh ho\u00e0n ch\u1ec9nh <br\/> Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh: <br\/> $3(x-1)+2=x$.","title_trans":"","temp":"sequence","correct":[[[4],[5],[1],[2],[3]]],"list":[{"point":5,"left":["$\\Leftrightarrow 2x=1$ $\\Leftrightarrow x=\\dfrac{1}{2}$"," Suy ra $x=\\dfrac{1}{2}$ l\u00e0 nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh","$3(x-1)+2=x$","$\\Leftrightarrow 3x-3+2=x$ $\\Leftrightarrow 3x-1=x$","$\\Leftrightarrow 3x-x=1$"],"top":75,"explain":"<span class='basic_left'> <b> Tr\u00ecnh t\u1ef1 s\u1eafp x\u1ebfp \u0111\u00fang c\u1ee7a b\u00e0i gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh l\u00e0: <\/b> <br\/> Ta c\u00f3: <br\/> $3(x-1)+2=x$ <br\/> $\\Leftrightarrow 3x-3+2=x$ <br\/> $\\Leftrightarrow 3x-1=x$ <br\/> $\\Leftrightarrow 3x-x=1$ <br\/> $\\Leftrightarrow 2x=1$ <br\/> $\\Leftrightarrow x=\\dfrac{1}{2}$ <br\/> Suy ra $x=\\dfrac{1}{2}$ l\u00e0 nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh "}]}],"id_ques":819},{"time":24,"part":[{"time":3,"title":"S\u1eafp x\u1ebfp c\u00e1c c\u00e2u \u0111\u1ec3 \u0111\u01b0\u1ee3c m\u1ed9t b\u00e0i gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh ho\u00e0n ch\u1ec9nh <br\/> Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh: <br\/> $3-(x-4)=2x$.","title_trans":"","temp":"sequence","correct":[[[5],[6],[4],[3],[2],[1]]],"list":[{"point":5,"left":["$\\Leftrightarrow 3x=7$ $ \\Leftrightarrow x=\\dfrac{7}{3}$"," Suy ra $x=\\dfrac{7}{3}$ l\u00e0 nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh","$\\Leftrightarrow -x-2x=-7$ $ \\Leftrightarrow -3x=-7$","$\\Leftrightarrow 7-x=2x$","$\\Leftrightarrow 3-x+4=2x$","$3-\\left( x-4 \\right)=2x$"],"top":75,"explain":"<span class='basic_left'> <b> Tr\u00ecnh t\u1ef1 s\u1eafp x\u1ebfp \u0111\u00fang c\u1ee7a b\u00e0i gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh l\u00e0: <\/b> <br\/> Ta c\u00f3: <br\/> $\\begin{align}& 3-\\left( x-4 \\right)=2x \\\\ & \\Leftrightarrow 3-x+4=2x \\\\ & \\Leftrightarrow 7-x=2x \\\\ & \\Leftrightarrow -x-2x=-7 \\\\ & \\Leftrightarrow -3x=-7 \\\\ & \\Leftrightarrow 3x=7 \\\\ & \\Leftrightarrow x=\\dfrac{7}{3} \\\\ \\end{align}$ <br\/> Suy ra $x=\\dfrac{7}{3}$ l\u00e0 nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh "}]}],"id_ques":820},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t ","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":" <span class='basic_left'> Ph\u01b0\u01a1ng tr\u00ecnh n\u00e0o sau \u0111\u00e2y t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi ph\u01b0\u01a1ng tr\u00ecnh $2x-4=0$? <\/span>","select":["A. $x^2-4=0$","B. $x-2=0$","C. $x^2-2x=0$","D. $6x+12=0$ "],"explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn<\/span><br\/> Bi\u1ebfn \u0111\u1ed5i ph\u01b0\u01a1ng tr\u00ecnh \u0111\u00e3 cho xem c\u00f3 th\u00e0nh ph\u01b0\u01a1ng tr\u00ecnh n\u00e0o trong c\u00e1c ph\u01b0\u01a1ng tr\u00ecnh trong \u0111\u00e1p \u00e1n kh\u00f4ng <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i<\/span> <br\/> Ta c\u00f3: $2x-4=0$ <br\/> $\\Leftrightarrow 2(x-2)=0$ <br\/> $\\Leftrightarrow x-2=0$ <br\/> Do \u0111\u00f3 ph\u01b0\u01a1ng tr\u00ecnh $2x-4=0$ v\u00e0 ph\u01b0\u01a1ng tr\u00ecnh $x-2=0$ t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi nhau <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 B <\/span> <br\/> <b> L\u01b0u \u00fd: <\/b> <i> \u0110\u1ec3 ch\u1ee9ng t\u1ecf hai ph\u01b0\u01a1ng tr\u00ecnh (1) v\u00e0 (2) t\u01b0\u01a1ng \u0111\u01b0\u01a1ng c\u00f3 hai c\u00e1ch hay d\u00f9ng: <br\/> <b> C\u00e1ch 1: <\/b> Ch\u1ee9ng t\u1ecf (1) v\u00e0 (2) c\u00f3 c\u00e1c t\u1eadp nghi\u1ec7m $S_1$ v\u00e0 $S_2$ b\u1eb1ng nhau. <br\/> <b> C\u00e1ch 2: <\/b> D\u00f9ng ph\u00e9p bi\u1ebfn \u0111\u1ed5i t\u01b0\u01a1ng \u0111\u01b0\u01a1ng \u0111\u1ec3 bi\u1ebfn (1) th\u00e0nh (2) ho\u1eb7c bi\u1ebfn \u0111\u1ed5i (2) th\u00e0nh (1). <\/i> <\/span> ","column":2}]}],"id_ques":821},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t ","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":" <span class='basic_left'> Ph\u01b0\u01a1ng tr\u00ecnh n\u00e0o sau \u0111\u00e2y t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi ph\u01b0\u01a1ng tr\u00ecnh $5x-2=x+6$? <\/span>","select":["A. $x^3+8=0$","B. $x-1=3x-3$","C. $(x-2)(x+2)=0$","D. $4(x-2)=0$ "],"explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn<\/span><br\/> Bi\u1ebfn \u0111\u1ed5i ph\u01b0\u01a1ng tr\u00ecnh \u0111\u00e3 cho xem c\u00f3 th\u00e0nh ph\u01b0\u01a1ng tr\u00ecnh n\u00e0o trong c\u00e1c ph\u01b0\u01a1ng tr\u00ecnh trong \u0111\u00e1p \u00e1n kh\u00f4ng? <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i<\/span> <br\/> Ta c\u00f3: $5x-2=x+6$ <br\/> $\\Leftrightarrow 5x-x=6+2$ <br\/> $\\Leftrightarrow 4x=8$ <br\/> $\\Leftrightarrow 4x-8=0$ <br\/> $\\Leftrightarrow 4(x-2)=0$ <br\/> Do \u0111\u00f3 ph\u01b0\u01a1ng tr\u00ecnh $5x-2=x+6$ v\u00e0 ph\u01b0\u01a1ng tr\u00ecnh $4(x-2)=0$ t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi nhau <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 D <\/span> <br\/> <b> L\u01b0u \u00fd: <\/b> <i> \u0110\u1ec3 ch\u1ee9ng t\u1ecf hai ph\u01b0\u01a1ng tr\u00ecnh (1) v\u00e0 (2) t\u01b0\u01a1ng \u0111\u01b0\u01a1ng c\u00f3 hai c\u00e1ch hay d\u00f9ng: <br\/> <b> C\u00e1ch 1: <\/b> Ch\u1ee9ng t\u1ecf (1) v\u00e0 (2) c\u00f3 c\u00e1c t\u1eadp nghi\u1ec7m $S_1$ v\u00e0 $S_2$ b\u1eb1ng nhau. <br\/> <b> C\u00e1ch 2: <\/b> D\u00f9ng ph\u00e9p bi\u1ebfn \u0111\u1ed5i t\u01b0\u01a1ng \u0111\u01b0\u01a1ng \u0111\u1ec3 bi\u1ebfn (1) th\u00e0nh (2) ho\u1eb7c bi\u1ebfn \u0111\u1ed5i (2) th\u00e0nh (1). <\/i> <\/span> ","column":2}]}],"id_ques":822},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["8"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<span class='basic_left'> Ph\u01b0\u01a1ng tr\u00ecnh $(x-3)(x+4)-2(3x-2)=(x-4)^2$ c\u00f3 t\u1eadp nghi\u1ec7m l\u00e0: $S=\\{\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}\\}$ <\/span> ","explain":" <span class='basic_left'> Ta c\u00f3: <br\/> $(x-3)(x+4)-2(3x-2)=(x-4)^2$ <br\/> $\\Leftrightarrow x^2+x-12-6x+4=x^2-8x+16$ <br\/> $\\Leftrightarrow -5x-8=-8x+16$ <br\/> $\\Leftrightarrow -5x+8x=16+8$ <br\/> $\\Leftrightarrow 3x=24$ <br\/> $\\Leftrightarrow x=8$ <br\/> T\u1eadp nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh l\u00e0: $S=\\{8\\}$ <br\/> <span class='basic_pink'> V\u1eady c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $8$ <\/span> <\/span> "}]}],"id_ques":823},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["1"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<span class='basic_left'> Ph\u01b0\u01a1ng tr\u00ecnh $\\dfrac{5x-2}{3}=\\dfrac{5-3x}{2}$ <br\/> c\u00f3 t\u1eadp nghi\u1ec7m l\u00e0: $S=\\{\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}\\}$ <\/span> ","explain":" <span class='basic_left'> Ta c\u00f3: <br\/> $\\begin{align} & \\dfrac{5x-2}{3}=\\dfrac{5-3x}{2} \\\\ & \\Leftrightarrow \\left( 5x-2 \\right)2=\\left( 5-3x \\right)3 \\\\ & \\Leftrightarrow 10x-4=15-9x \\\\ & \\Leftrightarrow 10x+9x=15+4 \\\\ & \\Leftrightarrow 19x=19 \\\\ & \\Leftrightarrow x=1 \\\\ \\end{align}$ <br\/> T\u1eadp nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh l\u00e0: $S=\\{1\\}$ <br\/> <span class='basic_pink'> V\u1eady c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $1$ <\/span> <\/span> "}]}],"id_ques":824},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["1"]]],"list":[{"point":5,"width":40,"type_input":"","input_hint":["frac"],"ques":"<span class='basic_left'> Ph\u01b0\u01a1ng tr\u00ecnh $\\dfrac{7x-1}{6}+2x=\\dfrac{16-x}{5}$ c\u00f3 t\u1eadp nghi\u1ec7m l\u00e0: $S=$ {_input_} <\/span> ","explain":" <span class='basic_left'> Ta c\u00f3: <br\/> $\\begin{align} & \\dfrac{7x-1}{6}+2x=\\dfrac{16-x}{5} \\\\ & \\Leftrightarrow \\left( 7x-1 \\right)5+2x.30=\\left( 16-x \\right)6 \\\\ & \\Leftrightarrow 35x-5+60x=96-6x \\\\ & \\Leftrightarrow 95x+6x=96+5 \\\\ & \\Leftrightarrow 101x=101 \\\\ & \\Leftrightarrow x=1 \\\\ \\end{align}$ <br\/> T\u1eadp nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh l\u00e0: $S=\\{1\\}$ <\/span> "}]}],"id_ques":825},{"time":24,"part":[{"title":"H\u00e3y \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng \u0111\u1ec3 \u0111\u01b0\u1ee3c m\u1ed9t ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n d\u1ea1ng $ax+b=0$","title_trans":"","temp":"fill_the_blank","correct":[[["3"],["-6"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<span class='basic_left'> Bi\u1ebft ph\u01b0\u01a1ng tr\u00ecnh c\u00f3 h\u1ec7 s\u1ed1 $a=3$ v\u00e0 c\u00f3 m\u1ed9t nghi\u1ec7m l\u00e0 $x=2$ <br\/> V\u1eady ph\u01b0\u01a1ng tr\u00ecnh c\u1ea7n t\u00ecm l\u00e0: $\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}x+\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}=0$ <\/span> ","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn<\/span><br\/> Thay gi\u00e1 tr\u1ecb c\u1ee7a $a$ v\u00e0 $x$ v\u00e0o ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n (d\u1ea1ng t\u1ed5ng qu\u00e1t) \u0111\u1ec3 t\u00ecm $b$ <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i<\/span> <br\/> Ta thay $a=3$ v\u00e0 $x=2$ v\u00e0o ph\u01b0\u01a1ng tr\u00ecnh $ax+b=0$ \u0111\u01b0\u1ee3c: <br\/> $3.2+b=0$ <br\/> $\\Leftrightarrow b=-6$ <br\/> $\\Rightarrow$ Ph\u01b0\u01a1ng tr\u00ecnh c\u1ea7n t\u00ecm c\u00f3 d\u1ea1ng: $3x-6=0$ <br\/> <span class='basic_pink'> V\u1eady c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u1ea7n l\u01b0\u1ee3t l\u00e0: $3$ v\u00e0 $-6$ <\/span> <\/span> "}]}],"id_ques":826},{"time":24,"part":[{"title":"H\u00e3y \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng \u0111\u1ec3 \u0111\u01b0\u1ee3c m\u1ed9t ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n d\u1ea1ng $ax+b=0$","title_trans":"","temp":"fill_the_blank","correct":[[["-2"],["10"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<span class='basic_left'> Bi\u1ebft ph\u01b0\u01a1ng tr\u00ecnh c\u00f3 h\u1ec7 s\u1ed1 $a=-2$ v\u00e0 c\u00f3 m\u1ed9t nghi\u1ec7m l\u00e0 $x=5$ <br\/> V\u1eady ph\u01b0\u01a1ng tr\u00ecnh c\u1ea7n t\u00ecm l\u00e0: $\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}x+\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}=0$ <\/span> ","explain":" <span class='basic_left'> Ta thay $a=-2$ v\u00e0 $x=5$ v\u00e0o ph\u01b0\u01a1ng tr\u00ecnh $ax+b=0$ \u0111\u01b0\u1ee3c: <br\/> $(-2).5+b=0$ <br\/> $\\Leftrightarrow -10+b=0$ <br\/> $\\Leftrightarrow b=10$ <br\/> $\\Rightarrow$ Ph\u01b0\u01a1ng tr\u00ecnh c\u1ea7n t\u00ecm c\u00f3 d\u1ea1ng: $-2x+10=0$ <br\/> <span class='basic_pink'> V\u1eady c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u1ea7n l\u01b0\u1ee3t l\u00e0: $-2$ v\u00e0 $10$ <\/span> <\/span> "}]}],"id_ques":827},{"time":24,"part":[{"title":"H\u00e3y \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng \u0111\u1ec3 \u0111\u01b0\u1ee3c m\u1ed9t ph\u01b0\u01a1ng tr\u00ecnh b\u1eadc nh\u1ea5t m\u1ed9t \u1ea9n d\u1ea1ng $ax+b=0$","title_trans":"","temp":"fill_the_blank","correct":[[["2"],["20"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<span class='basic_left'> Bi\u1ebft ph\u01b0\u01a1ng tr\u00ecnh c\u00f3 h\u1ec7 s\u1ed1 $b=20$ v\u00e0 c\u00f3 m\u1ed9t nghi\u1ec7m l\u00e0 $x=-10$ <br\/> Ph\u01b0\u01a1ng tr\u00ecnh c\u1ea7n t\u00ecm l\u00e0: $\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}x+\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}=0$ <\/span> ","explain":" <span class='basic_left'> Ta thay $b=20$ v\u00e0 $x=-10$ v\u00e0o ph\u01b0\u01a1ng tr\u00ecnh $ax+b=0$ \u0111\u01b0\u1ee3c: <br\/> $a.(-10)+20=0$ <br\/> $\\Leftrightarrow -10a+20=0$ <br\/> $\\Leftrightarrow a=2$ <br\/> $\\Rightarrow$ Ph\u01b0\u01a1ng tr\u00ecnh c\u1ea7n t\u00ecm c\u00f3 d\u1ea1ng: $2x+20=0$ <br\/> <span class='basic_pink'> V\u1eady c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u1ea7n l\u01b0\u1ee3t l\u00e0: $2$ v\u00e0 $20$ <\/span> <\/span> "}]}],"id_ques":828},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":" <span class='basic_left'> Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh: $3(|x|+5)-7=0$ <br\/> T\u1eadp nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh l\u00e0:<\/span>","select":["A. $S = \\mathbb{R}$","B. $S = \\varnothing$","C. $S = \\left\\{\\dfrac{8}{3}\\right\\}$","D. $S = \\left\\{ \\pm \\dfrac{8}{3}\\right\\}$"],"explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn<\/span><br\/> \u0110\u01b0a ph\u01b0\u01a1ng tr\u00ecnh \u0111\u00e3 cho v\u1ec1 d\u1ea1ng: $|x|=a$ $(a \\ge 0)$ <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i<\/span> <br\/> $\\begin{align} & 3\\left( |x|+5 \\right)-7=0 \\\\ & \\Leftrightarrow 3|x|+15-7=0 \\\\ & \\Leftrightarrow 3|x|+8=0 \\\\ & \\Leftrightarrow 3|x|=-8 \\\\ \\end{align}$ <br\/> Do $|x| \\ge 0$ v\u1edbi m\u1ecdi $x$ n\u00ean ph\u01b0\u01a1ng tr\u00ecnh v\u00f4 nghi\u1ec7m <br\/> Do \u0111\u00f3 ph\u01b0\u01a1ng tr\u00ecnh c\u00f3 t\u1eadp nghi\u1ec7m $ S = \\varnothing $ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 B <\/span> <\/span> ","column":2}]}],"id_ques":829},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t. ","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":" <span class='basic_left'> Gi\u1ea3i ph\u01b0\u01a1ng tr\u00ecnh $2(11-|x|)=7$ <br\/> T\u1eadp nghi\u1ec7m c\u1ee7a ph\u01b0\u01a1ng tr\u00ecnh l\u00e0: <\/span>","select":["A. $S = \\mathbb{R}$","B. $S = \\varnothing$","C. $S = \\left\\{\\pm \\dfrac{15}{2}\\right\\}$","D. $S = \\left\\{\\pm \\dfrac{2}{15}\\right\\}$"],"explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn<\/span><br\/> V\u1edbi $|A|=B$ $ (B > 0)$ th\u00ec ho\u1eb7c $A=B$ ho\u1eb7c $A=-B$ <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i<\/span> <br\/> $\\begin{align} & 2(11-|x|)=7 \\\\ & \\Leftrightarrow 22-2|x|=7 \\\\ & \\Leftrightarrow -2|x|=7-22 \\\\ & \\Leftrightarrow -2|x|=-15 \\\\ & \\Leftrightarrow 2|x|=15 \\\\ & \\Leftrightarrow |x|=\\dfrac{15}{2} \\\\ & \\Rightarrow x=\\pm \\dfrac{15}{2} \\\\ \\end{align}$ <br\/> Do \u0111\u00f3 ph\u01b0\u01a1ng tr\u00ecnh c\u00f3 t\u1eadp nghi\u1ec7m $ S= \\left\\{\\pm \\dfrac{15}{2}\\right\\}$ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 C <\/span> <\/span> ","column":2}]}],"id_ques":830}],"lesson":{"save":0,"level":2}}