{"segment":[{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t.<br\/> Kh\u1eb3ng \u0111\u1ecbnh d\u01b0\u1edbi \u0111\u00e2y \u0111\u00fang hay sai","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/16.jpg' \/><\/center> $(6x^2-3x+5):(2x-1)=3x$ d\u01b0 $5$ ","select":["\u0110\u00fang","Sai"],"hint":"","explain":"<span class='basic_left'><span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/>Trong ph\u00e9p chia c\u00f3 d\u01b0: $a:b=p$ d\u01b0 $r$ ta lu\u00f4n c\u00f3: $a=b.p+r$<\/span><br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/><span class='basic_left'>Ta c\u00f3:<br\/> $3x.(2x-1)+5=6x^2-3x+5$ <span><br\/> <span class='basic_pink'> V\u1eady kh\u1eb3ng \u0111\u1ecbnh tr\u00ean l\u00e0: \u0110\u00fang.<\/span>","column":2}]}],"id_ques":701},{"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":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/8.jpg' \/><\/center> \u0110\u1ec3 $(x^4+ax^3+bx-1)\\,\\vdots \\,( x^2-1)$ th\u00ec: ","select":["A. $a=b; b\\in \\mathbb{R}$","B. $a=5;b=6$","C. $a=b=10$","D. $a \\in \\mathbb{R};b=-a$"],"hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1:<\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p chia $(x^4+ax^3+bx-1)\\,: \\,( x^2-1)$, t\u00ecm s\u1ed1 d\u01b0.<br\/> <b> B\u01b0\u1edbc 2:<\/b> Cho s\u1ed1 d\u01b0 \u0111\u00f3 b\u1eb1ng $0$ \u0111\u1ec3 t\u00ecm $a$. <br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/> Ta c\u00f3:<br\/> $\\left. \\begin{align} & \\begin{matrix} \\,\\,\\,\\,\\,\\,\\,\\,\\,{{x}^{4}}+a\\,{{x}^{3}}+bx-1 \\\\ {{x}^{4}}\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,-{{x}^{2}} \\\\\\end{matrix} \\\\ & \\overline{\\begin{align} & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,a\\,{{x}^{3}}+{{x}^{2}}+bx-1 \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,a\\,{{x}^{3}}\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,-ax \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\overline{\\begin{align} & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,{{x}^{2}}+\\left( a+b \\right)x-1 \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,{{x}^{2}}\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,-1 \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\overline{\\,\\,\\,\\,\\,\\,\\,\\,\\,\\left( a+b \\right)x\\,\\,\\,\\,\\,} \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\, \\\\ \\end{align}} \\\\ \\end{align}} \\\\ \\end{align} \\right|\\begin{matrix} \\dfrac{{{x}^{2}}-1}{{{x}^{2}}+a\\,x+1} \\\\ \\begin{matrix} \\begin{matrix} \\begin{matrix} \\begin{matrix} {} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\\\end{matrix}$ <br\/> V\u1eady $(x^4+ax^3+bx-1)\\,: \\,( x^2-1)=x^2+ax+1$ d\u01b0 $(a+b)x$.<br\/> \u0110\u1ec3 ph\u00e9p chia $ (x^4+ax^3+bx-1)\\,: \\,( x^2-1)$ l\u00e0 ph\u00e9p chia h\u1ebft th\u00ec <br\/>$(a+b)x=0\\Rightarrow \\left\\{ \\begin{aligned} & a\\,\\,\\text{t\u00f9y \u00fd} \\\\ & a+b=0 \\\\ \\end{aligned} \\right. \\Leftrightarrow \\left\\{ \\begin{aligned} & a \\in \\mathbb{R} \\\\ & b=-a \\\\ \\end{aligned} \\right.$ <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 D. <\/span><\/span> ","column":2}]}],"id_ques":702},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o \u00f4 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["x-2","-2+x"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/4.jpg' \/><\/center> Ph\u00e9p chia $\\left( 12x^3+14x^2-4x-8\\right)$$:(4x^2+2x-3)$ c\u00f3 d\u01b0 l\u00e0 _input_","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> \u0110\u1eb7t ph\u00e9p chia v\u00e0 t\u00ecm s\u1ed1 d\u01b0.<br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/> Ta c\u00f3: <br\/>$\\left. \\begin{align} & \\begin{matrix} 12{{x}^{3}}+14{{x}^{2}}-4x-8\\,\\,\\,\\,\\,\\, \\\\ 12{{x}^{3}}+6{{x}^{2}}\\,\\,-9x\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\, \\\\\\end{matrix} \\\\ & \\overline{\\begin{align} & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,8{{x}^{2}}+5x-8\\,\\,\\,\\,\\,\\,\\,\\,\\, \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,8{{x}^{2}}+4x-6 \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\overline{\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,x-2\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,} \\\\ \\end{align}} \\\\ \\end{align} \\right|\\begin{matrix} \\dfrac{4{{x}^{2}}+2x-3}{3x+2} \\\\ \\begin{matrix} {} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\\\end{matrix}$ <br\/> Ph\u00e9p chia c\u00f3 d\u01b0 l\u00e0 $x-2$<br\/> <span class='basic_pink'> Do \u0111\u00f3 d\u01b0 ph\u1ea3i \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $x-2$. <\/span><\/span> "}]}],"id_ques":703},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o \u00f4 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["3x+2","2+3x"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/5.jpg' \/><\/center> Ph\u00e9p chia $\\left( 6x^4+15x^3+7x^2+2 \\right):(2x^2+3x)$ c\u00f3 d\u01b0 l\u00e0 _input_","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> \u0110\u1eb7t ph\u00e9p chia v\u00e0 t\u00ecm s\u1ed1 d\u01b0.<br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/> Ta c\u00f3:<br\/>$\\left. \\begin{aligned}& \\begin{matrix} 6{{x}^{4}}+15{{x}^{3}}+7{{x}^{2}}\\,\\,\\,\\,\\,\\,\\,\\,+2 \\\\6{{x}^{4}}+9{{x}^{3}}\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\, \\\\\\end{matrix} \\\\ & \\overline{\\begin{aligned}& \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,6{{x}^{3}}+7{{x}^{2}}\\,\\,\\,\\,\\,\\,\\,\\,+2 \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,6{{x}^{3}}+9{{x}^{2}} \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\overline{\\begin{aligned} & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,-2{{x}^{2}}\\,\\,\\,\\,\\,\\,\\,+2 \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,-2{{x}^{2}}-3x \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\overline{\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,3x+2\\,\\,\\,\\,} \\\\ \\end{aligned}} \\\\ \\end{aligned}} \\\\ \\end{aligned} \\right|\\begin{matrix} \\dfrac{2{{x}^{2}}+3x}{3{{x}^{2}}+3x-1} \\\\\\begin{matrix} \\begin{matrix} \\begin{matrix} {} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\\\end{matrix} \\\\{} \\\\\\end{matrix}$<br\/> Ph\u00e9p chia c\u00f3 d\u01b0 l\u00e0 $3x+2$. <br\/> <span class='basic_pink'> Do \u0111\u00f3 d\u01b0 ph\u1ea3i \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $3x+2$. <\/span><\/span> "}]}],"id_ques":704},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o \u00f4 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["4x+2","2+4x"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/4.jpg' \/><\/center> Ph\u00e9p chia $\\left( 12x^4-3x^3-16x^2+8x+2 \\right)$$:(3x^2-4)$ c\u00f3 d\u01b0 l\u00e0 _input_","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> \u0110\u1eb7t ph\u00e9p chia v\u00e0 t\u00ecm s\u1ed1 d\u01b0.<br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/>Ta c\u00f3:<br\/>$\\left. \\begin{aligned}& \\begin{matrix} 12{{x}^{4}}-3{{x}^{3}}-16{{x}^{2}}+8x+2 \\\\12{{x}^{4}}\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,-16{{x}^{2}}\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\, \\\\\\end{matrix} \\\\ & \\overline{\\begin{aligned} & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,-3{{x}^{3}}\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,+8x+2 \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,-3{{x}^{3}}\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,+4x \\\\ &\\,\\,\\,\\,\\,\\,\\,\\,\\overline{\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,4x+2\\,\\,\\,\\,\\,} \\\\ \\end{aligned}} \\\\ \\end{aligned} \\right|\\begin{matrix} \\dfrac{3{{x}^{2}}-4}{4{{x}^{2}}-x} \\\\ \\begin{matrix} {} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\\\end{matrix}$<br\/> Ph\u00e9p chia c\u00f3 d\u01b0 l\u00e0 $4x+2$. <br\/> <span class='basic_pink'> Do \u0111\u00f3 d\u01b0 ph\u1ea3i \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $4x+2$. <\/span><\/span> "}]}],"id_ques":705},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o \u00f4 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["2x+3","3+2x"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/3.jpg' \/><\/center> Ph\u00e9p chia $\\left( 15x^4+6x^3+10x^2+6x+3 \\right):(3x^2+2)$ c\u00f3 d\u01b0 l\u00e0 _input_","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> \u0110\u1eb7t ph\u00e9p chia v\u00e0 t\u00ecm s\u1ed1 d\u01b0.<br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/>Ta c\u00f3:<br\/>$\\begin{matrix} \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,15{{x}^{4}}+6{{x}^{3}}+10{{x}^{2}}+\\,6x+3 \\\\ \\begin{matrix} 15{{x}^{4}}\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,+10{{x}^{2}} \\,\\,\\,\\,\\\\ \\overline{\\dfrac{\\begin{matrix} \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,6{{x}^{3}}\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,+6x+3 \\\\ \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,6{{x}^{3}}\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,+4x \\\\ \\end{matrix}}{\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,2x+3}} \\\\ \\end{matrix} \\\\ \\end{matrix}\\left| \\begin{matrix} \\dfrac{3{{x}^{2}}+2}{5{{x}^{2}}+2x} \\\\ {} \\\\ {} \\\\ {} \\\\\\end{matrix} \\right.$<br\/> Ph\u00e9p chia c\u00f3 d\u01b0 l\u00e0 $2x+3$. <br\/> <span class='basic_pink'> Do \u0111\u00f3 ph\u1ea3i d\u01b0 \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $2x+3$. <\/span><\/span> "}]}],"id_ques":706},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o \u00f4 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["2"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/2.jpg' \/><\/center>Bi\u1ebft $(y^3+8):(y+2)-2y=0$, gi\u00e1 tr\u1ecb c\u1ee7a $y$ l\u00e0 _input_","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1:<\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p chia $(y^3+8):(y+2)$, ph\u00e2n t\u00edch $y^3+8$ theo h\u1eb1ng \u0111\u1eb3ng th\u1ee9c t\u1ed5ng hai l\u1eadp ph\u01b0\u01a1ng.<br\/> <b> B\u01b0\u1edbc 2:<\/b> R\u00fat g\u1ecdn \u0111\u1ec3 t\u00ecm gi\u00e1 tr\u1ecb c\u1ee7a $y$. <br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/> Ta c\u00f3:<br\/> $ (y^3+8):(y+2)-2y =0 \\\\ \\Leftrightarrow (y+2)(y^2-2y+4):(y+2)-2y=0 \\\\ \\Leftrightarrow y^2-2y+4-2y =0 \\\\ \\Leftrightarrow y^2-4y+4 =0 \\\\ \\Leftrightarrow (y-2)^2 =0 \\\\ \\Leftrightarrow y-2 =0 \\\\ \\Leftrightarrow y =2 $ <br\/> <span class='basic_pink'> Do \u0111\u00f3 s\u1ed1 ph\u1ea3i \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $2$. <\/span><\/span> "}]}],"id_ques":707},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o \u00f4 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["3"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/16.jpg' \/><\/center>Bi\u1ebft $(3x^4+11x^3-5x^2-19x+10):(x^2+3x-2)-3x^2=1$, gi\u00e1 tr\u1ecb c\u1ee7a $x$ l\u00e0 _input_","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1:<\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p chia $(3x^4+11x^3-5x^2-19x+10):(x^2+3x-2)$<br\/> <b> B\u01b0\u1edbc 2:<\/b> R\u00fat g\u1ecdn \u0111\u1ec3 t\u00ecm gi\u00e1 tr\u1ecb c\u1ee7a $x$. <br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/> Ta c\u00f3:<br\/> $\\begin{matrix} \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,3{{x}^{4}}+11{{x}^{3}}-5{{x}^{2}}-\\,19x+10 \\\\ \\begin{matrix} 3{{x}^{4}}+9{{x}^{3}}-6{{x}^{2}} \\\\ \\overline{\\dfrac{\\begin{matrix} \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,2{{x}^{3}}+{{x}^{2}}-19x+10 \\\\ \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,2{{x}^{3}}+6{{x}^{2}}-4x \\\\ \\end{matrix}}{\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\dfrac{\\begin{matrix} -5{{x}^{2}}-15x+10 \\\\ -5{{x}^{2}}-15x+10 \\\\\\end{matrix}}{0}}} \\\\\\end{matrix} \\\\\\end{matrix}\\left| \\begin{matrix} \\dfrac{{{x}^{2}}+3x-2}{3{{x}^{2}}+2x-5} \\\\ \\begin{matrix} {} \\\\ {} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\ {} \\\\\\end{matrix} \\right.$<br\/> Khi \u0111\u00f3: <br\/> $\\begin{align} &(3x^4+11x^3-5x^2-19x+10) :(x^2+3x-2)-3x^2 =1\\\\ \\Leftrightarrow\\, &3x^2+2x-5-3x^2 =1 \\\\ \\Leftrightarrow \\, &2x-5 =1 \\\\ \\Leftrightarrow \\,&2x =6 \\\\ \\Leftrightarrow \\,&x =3 \\end{align} $ <br\/> <span class='basic_pink'> Do \u0111\u00f3 s\u1ed1 ph\u1ea3i \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $3$. <\/span><\/span> "}]}],"id_ques":708},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o \u00f4 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["3"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/16.jpg' \/><\/center>Bi\u1ebft $(8x^2-12x):(2x-3)-12=0$, gi\u00e1 tr\u1ecb c\u1ee7a $x$ l\u00e0 _input_","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1:<\/b> Ph\u00e2n t\u00edch $8x^2-12x$ b\u1eb1ng c\u00e1ch \u0111\u1eb7t nh\u00e2n t\u1eed chung.<br\/> <b> B\u01b0\u1edbc 2:<\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p chia v\u00e0 t\u00ecm gi\u00e1 tr\u1ecb c\u1ee7a $x$. <br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/>Ta c\u00f3:<br\/> $ (8x^2-12x):(2x-3)-12=0 \\\\ \\Leftrightarrow 4x(2x-3):(2x-3)-12=0 \\\\ \\Leftrightarrow 4x-12 =0 \\\\ \\Leftrightarrow 4x =12 \\\\ \\Leftrightarrow x=3$ <br\/> <span class='basic_pink'> Do \u0111\u00f3 s\u1ed1 ph\u1ea3i \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $3$. <\/span><\/span> "}]}],"id_ques":709},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["7"]]],"list":[{"point":5,"width":50,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/13.jpg' \/><\/center> \u0110\u1ec3 ph\u00e9p chia $(x^4-x^3+6x^2-x+m):(x^2-x+5)$ c\u00f3 d\u01b0 l\u00e0 $2$ th\u00ec $m$ = _input_ ","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1:<\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p chia $(x^4-x^3+6x^2-x+m)$$:(x^2-x+5)$, t\u00ecm s\u1ed1 d\u01b0.<br\/> <b> B\u01b0\u1edbc 2:<\/b> Cho s\u1ed1 d\u01b0 \u0111\u00f3 b\u1eb1ng $2$ \u0111\u1ec3 t\u00ecm $m$. <br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/> Ta c\u00f3: <br\/>$\\begin{matrix} \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,{{x}^{4}}-{{x}^{3}}+6{{x}^{2}}-\\,x+m \\\\ \\begin{matrix} {{x}^{4}}-{{x}^{3}}+5{{x}^{2}} \\\\ \\overline{\\dfrac{\\begin{matrix} \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,{{x}^{2}}-x+m \\\\ \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,{{x}^{2}}-x+5 \\\\\\end{matrix}}{\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,m-5}} \\\\\\end{matrix} \\\\\\end{matrix}\\left| \\begin{matrix} \\dfrac{{{x}^{2}}-x+5}{{{x}^{2}}+1} \\\\ {} \\\\ {} \\\\ {} \\\\\\end{matrix} \\right.$<br\/> V\u1eady $(x^4-x^3+6x^2-x+m)$$:(x^2-x+5)=x^2+1$ d\u01b0 $m-5$.<br\/> \u0110\u1ec3 ph\u00e9p chia c\u00f3 d\u01b0 l\u00e0 $2$ th\u00ec $m-5=2\\Rightarrow m=7$ <br\/> <span class='basic_pink'> Do \u0111\u00f3 s\u1ed1 ph\u1ea3i \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $7$. <\/span><\/span> "}]}],"id_ques":710},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["-25"],["4"]]],"list":[{"point":5,"width":50,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/12.jpg' \/><\/center> \u0110\u1ec3 ph\u00e9p chia $(6x^4-x^3+ax^2+bx+4):(x^2-4)$ l\u00e0 ph\u00e9p chia h\u1ebft th\u00ec $\\left\\{ \\begin{align} & a= \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}\\\\ & b= \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}\\\\ \\end{align} \\right.$ ","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1:<\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p chia $(6x^4-x^3+ax^2+bx+4):(x^2-4)$, t\u00ecm s\u1ed1 d\u01b0.<br\/> <b> B\u01b0\u1edbc 2:<\/b> Cho s\u1ed1 d\u01b0 \u0111\u00f3 b\u1eb1ng $0$ \u0111\u1ec3 t\u00ecm $a, b$. <br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/> Ta c\u00f3: <br\/>$\\left. \\begin{align} & \\begin{matrix} 6{{x}^{4}}-{{x}^{3}}+a{{x}^{2}}+bx+4\\,\\,\\,\\,\\,\\,\\,\\,\\, \\\\ 6{{x}^{4}}-24{{x}^{2}}\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\, \\\\\\end{matrix} \\\\ & \\overline{\\begin{align} & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,-{{x}^{3}}+\\left( a+24 \\right){{x}^{2}}+bx+4\\,\\,\\, \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,-{{x}^{3}}\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,+4x\\,\\, \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\overline{\\begin{align} & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\left( a+24 \\right){{x}^{2}}+\\left( b-4 \\right)x+4\\,\\,\\, \\\\ & \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\left( a+24 \\right){{x}^{2}}-4a-96 \\\\ &\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\overline{\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\left( b-4 \\right)x+4a+100\\,\\,}\\, \\\\ \\end{align}} \\\\ \\end{align}} \\\\ \\end{align} \\right|\\begin{matrix} \\dfrac{{{x}^{2}}-4}{6{{x}^{2}}-x+a+24} \\\\ \\begin{matrix} \\begin{matrix} \\begin{matrix} {} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\\\end{matrix}$<br\/> V\u1eady $(6x^4-x^3+ax^2+bx+4):(x^2-4)$$=6x^2-x+a+24$ d\u01b0 $(b-4)x+4a+100$.<br\/> \u0110\u1ec3 \u0111\u00e2y l\u00e0 ph\u00e9p chia h\u1ebft th\u00ec $\\left\\{ \\begin{aligned} & b-4=0 \\\\ & 4a+100=0 \\\\ \\end{aligned} \\right.\\Rightarrow \\left\\{ \\begin{aligned} & a=-25 \\\\ & b=4 \\\\ \\end{aligned} \\right.$ <br\/> <span class='basic_pink'> Do \u0111\u00f3 s\u1ed1 ph\u1ea3i \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $-25; 4$. <\/span><\/span> "}]}],"id_ques":711},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["-2"],["0"]]],"list":[{"point":5,"width":50,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/11.jpg' \/><\/center> \u0110\u1ec3 ph\u00e9p chia $(2x^3+2x^2+ax+b):(x^2+x-1)$ l\u00e0 ph\u00e9p chia h\u1ebft th\u00ec $\\left\\{ \\begin{align} & a= \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}\\\\ & b= \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}\\\\ \\end{align} \\right.$ ","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1:<\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p chia $(2x^3+2x^2+ax+b):(x^2+x-1)$, t\u00ecm s\u1ed1 d\u01b0.<br\/> <b> B\u01b0\u1edbc 2:<\/b> Cho s\u1ed1 d\u01b0 \u0111\u00f3 b\u1eb1ng $0$ \u0111\u1ec3 t\u00ecm $a, b$. <br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/> Ta c\u00f3:<br\/> $\\begin{matrix} \\,\\,\\,\\,\\,\\,\\,2{{x}^{3}}+2{{x}^{2}}+ax+b \\\\ \\begin{matrix} 2{{x}^{3}}+2{{x}^{2}}-2x \\\\ \\overline{\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\left( a+2 \\right)x+b} \\\\\\end{matrix} \\\\\\end{matrix}\\left| \\begin{matrix} \\dfrac{{{x}^{2}}+x-1}{2x} \\\\ \\begin{matrix} {} \\\\ {} \\\\\\end{matrix} \\\\\\end{matrix} \\right.$<br\/> V\u1eady $(2x^3+2x^2+ax+b):(x^2+x-1)$$=2x$ d\u01b0 $(a+2)x+b$.<br\/> \u0110\u1ec3 \u0111\u00e2y l\u00e0 ph\u00e9p chia h\u1ebft th\u00ec $\\left\\{ \\begin{aligned} & a+2=0 \\\\ & b=0 \\\\ \\end{aligned} \\right.\\Rightarrow \\left\\{ \\begin{aligned} & a=-2 \\\\ & b=0 \\\\ \\end{aligned} \\right.$ <br\/> <span class='basic_pink'> Do \u0111\u00f3 s\u1ed1 ph\u1ea3i \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $-2; 0$. <\/span><\/span> "}]}],"id_ques":712},{"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":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/10.jpg' \/><\/center> K\u1ebft qu\u1ea3 ph\u00e9p chia $(25x^3+25x^2+29x+5)$$:(5x+1)$ l\u00e0: ","select":["A. $5x^2-3x+1$ ","B. $5x^2+4x+5$ ","C. $5x^2+29x-1$","D. $5x^2+25x+5$"],"hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn<\/span><br\/> \u0110\u1eb7t ph\u00e9p chia $(25x^3+25x^2+29x+5):(5x+1)$ <br\/><span class='basic_green'>Gi\u1ea3i<\/span><br\/><span class='basic_left'>Ta c\u00f3:<br\/> $\\begin{matrix} \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,25{{x}^{3}}+25{{x}^{2}}+\\,29x+5 \\\\ \\begin{matrix} 25{{x}^{3}}+5{{x}^{2}} \\\\ \\overline{\\dfrac{\\begin{matrix} \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,20{{x}^{2}}+29x+5 \\\\ \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,20{{x}^{2}}+4x \\\\ \\end{matrix}}{\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\dfrac{\\begin{matrix} 25x+5 \\\\ 25x+5 \\\\\\end{matrix}}{0}}} \\\\\\end{matrix} \\\\\\end{matrix}\\left| \\begin{matrix} \\dfrac{5x+1}{5{{x}^{2}}+4x+5} \\\\ \\begin{matrix} \\begin{matrix} {} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\\\end{matrix} \\\\ {} \\\\ {} \\\\\\end{matrix} \\right.$ <span><br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span>","column":2}]}],"id_ques":713},{"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":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/9.jpg' \/><\/center> K\u1ebft qu\u1ea3 ph\u00e9p chia $(8x^3-16x^2+8x):(4x-4)$ l\u00e0: ","select":["A. $2x(x+1)$ ","B. $2x^2-2x$ ","C. $2x^2+1$","D. $2x^2-4x$"],"hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn<\/span><br\/> <b> B\u01b0\u1edbc 1:<\/b> Ph\u00e2n t\u00edch \u0111a th\u1ee9c $8x^3-16x^2+8x$ v\u00e0 $4x - 4$ th\u00e0nh nh\u00e2n t\u1eed<br\/> <b> B\u01b0\u1edbc 2:<\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p chia sau khi ph\u00e2n t\u00edch. <br\/><span class='basic_green'>Gi\u1ea3i<\/span><br\/><span class='basic_left'>Ta c\u00f3 :<br\/> $\\begin{align} & (8{{x}^{3}}-16{{x}^{2}}+8x):(4x-4) \\\\ & =8x\\left( {{x}^{2}}-2x+1 \\right):4\\left( x-1 \\right) \\\\ & =8x{{\\left( x-1 \\right)}^{2}}:4\\left( x-1 \\right) \\\\ & =2x\\left( x-1 \\right) \\\\ & =2{{x}^{2}}-2x \\\\ \\end{align}$ <span><br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span>","column":2}]}],"id_ques":714},{"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":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/8.jpg' \/><\/center> K\u1ebft qu\u1ea3 ph\u00e9p chia $(12x^3-9x^2-3x):(3x-3)$ l\u00e0: ","select":["A. $(x+1)(4x+1)$ ","B. $4x+1$ ","C. $3x(4x+1)$","D. $x(4x+1)$"],"hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn<\/span><br\/> <b> B\u01b0\u1edbc 1:<\/b> Ph\u00e2n t\u00edch \u0111a th\u1ee9c $12x^3-9x^2-3x$ v\u00e0 $3x - 3$ th\u00e0nh nh\u00e2n t\u1eed. <br\/> <b> B\u01b0\u1edbc 2:<\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p chia sau khi ph\u00e2n t\u00edch. <br\/><span class='basic_green'>Gi\u1ea3i<\/span><br\/><span class='basic_left'>Ta c\u00f3 :<br\/> $\\begin{align} & (12{{x}^{3}}-9{{x}^{2}}-3x):(3x-3) \\\\ & =3x\\left( 4{{x}^{2}}-3x-1 \\right):3\\left( x-1 \\right) \\\\ & =x\\left( 4{{x}^{2}}-4x+x-1 \\right):\\left( x-1 \\right) \\\\ & =x\\left[ 4x\\left( x-1 \\right)+\\left( x-1 \\right) \\right]:\\left( x-1 \\right) \\\\ & =x\\left( x-1 \\right)\\left( 4x+1 \\right):\\left( x-1 \\right) \\\\ & =x\\left( 4x+1 \\right) \\\\ \\end{align}$ <span><br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span>","column":2}]}],"id_ques":715},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng \u0111\u1ec3 ho\u00e0n th\u00e0nh ph\u00e9p chia sau ","title_trans":"","temp":"fill_the_blank","correct":[[["a"],["b"]]],"list":[{"point":5,"width":50,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/4.jpg' \/><\/center> $[(a-b)^3-(a-b)]:(\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}-\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{})=(a-b)^2-1$","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1:<\/b> \u0110\u1eb7t $a-b$ l\u00e0 nh\u00e2n t\u1eed chung c\u1ee7a $(a-b)^3-(a-b)$. <br\/> <b> B\u01b0\u1edbc 2:<\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p chia $[(a-b)^3-(a-b)]:[(a-b)^2-1]$. <br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/> Ta c\u00f3: <br\/> $ [{{(a-b)}^{3}}-(a-b)]:[{{(a-b)}^{2}}-1] $<br\/>$ =\\left( a-b \\right)\\left[ {{\\left( a-b \\right)}^{2}}-1 \\right]:[{{(a-b)}^{2}}-1] $<br\/>$ =a-b $ <br\/> <span class='basic_pink'> Do \u0111\u00f3 s\u1ed1 ph\u1ea3i \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $a$ v\u00e0 $b$. <\/span><\/span> "}]}],"id_ques":716},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng \u0111\u1ec3 ho\u00e0n th\u00e0nh ph\u00e9p chia sau ","title_trans":"","temp":"fill_the_blank","correct":[[["4x+5","5+4x"]]],"list":[{"point":5,"width":50,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/5.jpg' \/><\/center> $(12x^3+27x^2+15x):(\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}) =3x(x+1)$","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1:<\/b> Ph\u00e2n t\u00edch $12x^3+27x^2+15x$ th\u00e0nh nh\u00e2n t\u1eed b\u1eb1ng c\u00e1ch t\u00e1ch $27x^2=12x^2+15x^2$ r\u1ed3i nh\u00f3m v\u00e0 \u0111\u1eb7t nh\u00e2n t\u1eed chung. <br\/> <b> B\u01b0\u1edbc 2:<\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p chia $(12x^3+27x^2+15x):3x(x+1)$. <br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/> Ta c\u00f3: <br\/> $ (12{{x}^{3}}+27{{x}^{2}}+15x):3x(x+1) $<br\/>$ =\\left( 12{{x}^{3}}+12{{x}^{2}}+15{{x}^{2}}+15x \\right):3x\\left( x+1 \\right) $<br\/>$ =\\left[ 12{{x}^{2}}\\left( x+1 \\right)+15x\\left( x+1 \\right) \\right]:3x\\left( x+1 \\right) $<br\/>$ =\\left[ 3x\\left( x+1 \\right)\\left( 4x+5 \\right) \\right]$$:3x\\left( x+1 \\right) $<br\/>$ =4x+5 $ <br\/> <span class='basic_pink'> Do \u0111\u00f3 s\u1ed1 ph\u1ea3i \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $4x+5$. <\/span><\/span> "}]}],"id_ques":717},{"time":24,"part":[{"title":"Ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"select":["A. $\\dfrac{x}{5} + 3y$","B. $\\dfrac{x^2}{5} + 3y$","C. $\\dfrac{x}{5} + 3$"],"ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/3.jpg' \/><\/center> K\u1ebft qu\u1ea3 ph\u00e9p chia <br\/> $\\left( \\dfrac{{{x}^{2}}}{25}-9{{y}^{2}} \\right):\\left( \\dfrac{x}{5}-3y \\right)= ?$","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1:<\/b> Ph\u00e2n t\u00edch $\\dfrac{{{x}^{2}}}{25}-9{{y}^{2}}$ th\u00e0nh nh\u00e2n t\u1eed theo h\u1eb1ng \u0111\u1eb3ng th\u1ee9c $a^2-b^2=(a+b)(a-b)$.<br\/> <b> B\u01b0\u1edbc 2:<\/b>\u00c1p d\u1ee5ng $(a.b):b=a$ \u0111\u1ec3 th\u1ef1c hi\u1ec7n ph\u00e9p chia. <br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/> Ta c\u00f3:<br\/>$\\begin{align} & \\left( \\dfrac{{{x}^{2}}}{25}-9{{y}^{2}} \\right):\\left( \\dfrac{x}{5}-3y \\right) \\\\ & =\\left[ \\left( \\dfrac{x}{5}+3y \\right)\\left( \\dfrac{x}{5}-3y \\right) \\right]:\\left( \\dfrac{x}{5}-3y \\right) \\\\ & =\\dfrac{x}{5}+3y \\\\ \\end{align}$ <\/span> "}]}],"id_ques":718},{"time":24,"part":[{"title":"Ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"select":["A. $x^2+3$","B. $x^3+3$","C. $x^4+3$"],"ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/3.jpg' \/><\/center> K\u1ebft qu\u1ea3 ph\u00e9p chia <br\/> $x^2(x^6+3x^2):x^4 = ?$","hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> B\u01b0\u1edbc 1:<\/b> Ph\u00e2n t\u00edch $x^6+3x^2$ th\u00e0nh nh\u00e2n t\u1eed b\u1eb1ng c\u00e1ch \u0111\u1eb7t nh\u00e2n t\u1eed chung.<br\/> <b> B\u01b0\u1edbc 2:<\/b> \u00c1p d\u1ee5ng $(a.b):b=a$ \u0111\u1ec3 th\u1ef1c hi\u1ec7n ph\u00e9p chia. <br\/><span class='basic_green'>B\u00e0i gi\u1ea3i<\/span><br\/> Ta c\u00f3: <br\/>$[x^2(x^6+3x^2)]:x^4=[x^2.x^2(x^4+3)]:x^4$$=[x^4(x^4+3)]:x^4$$=x^4+3$<\/span> "}]}],"id_ques":719},{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o \u00f4 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["x-2","-2+x","2-x","-x+2"]]],"list":[{"point":5,"width":50,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai9/lv2/img\/2.jpg' \/><\/center> K\u1ebft qu\u1ea3 ph\u00e9p chia <br\/> $(x-2)^3:(x-2)=$(_input_)$^2$","hint":" \u00c1p d\u1ee5ng $a^3:a=a^2$.","explain":"<span class='basic_left'>Ta c\u00f3:<br\/>$(x-2)^3:(x-2)=(x-2)^2$. <br\/> <span class='basic_pink'> Do \u0111\u00f3 ph\u1ea3i \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $x-2$. <\/span><\/span> "}]}],"id_ques":720}],"lesson":{"save":0,"level":2}}