{"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":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai1/lv2/img\/1.png' \/><\/center>K\u1ebft qu\u1ea3 c\u1ee7a ph\u00e9p nh\u00e2n $-5{{x}^{3}}\\left( 1-\\dfrac{11}{5}{{x}^{7}}+5{{x}^{3}} \\right)$ c\u00f3 h\u1ec7 s\u1ed1 cao nh\u1ea5t l\u00e0 $11$","select":["\u0110\u00fang","Sai"],"hint":"Trong \u0111a th\u1ee9c m\u1ed9t bi\u1ebfn: H\u1ec7 s\u1ed1 cao nh\u1ea5t l\u00e0 h\u1ec7 s\u1ed1 \u0111i v\u1edbi l\u0169y th\u1eeba b\u1eadc cao nh\u1ea5t c\u1ee7a bi\u1ebfn","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/>Ta th\u1ef1c hi\u1ec7n ph\u00e9p nh\u00e2n \u0111\u01a1n th\u1ee9c v\u1edbi \u0111a th\u1ee9c \u0111\u1ec3 bi\u1ebfn \u0111\u1ed5i bi\u1ec3u th\u1ee9c.<br\/>S\u1eafp x\u1ebfp bi\u1ec3u th\u1ee9c thu \u0111\u01b0\u1ee3c theo th\u1ee9 t\u1ef1 l\u0169y th\u1eeba gi\u1ea3m d\u1ea7n c\u1ee7a bi\u1ebfn x, r\u1ed3i t\u00ecm h\u1ec7 s\u1ed1 cao nh\u1ea5t.<br\/><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/>$-5{{x}^{3}}\\left( 1-\\dfrac{11}{5}{{x}^{7}}+5{{x}^{3}} \\right) \\\\ =-5{{x}^{3}}+11{{x}^{10}}-25{{x}^{6}} \\\\ =11{{x}^{10}}-25{{x}^{6}}-5{{x}^{3}}$<br\/>L\u0169y th\u1eeba cao nh\u1ea5t c\u1ee7a bi\u1ebfn trong \u0111a th\u1ee9c l\u00e0 $10$ . Do \u0111\u00f3 h\u1ec7 s\u1ed1 cao nh\u1ea5t l\u00e0 $11$.<br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 \u0110\u00fang.<\/span>","column":2}]}],"id_ques":301},{"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/bai1/lv2/img\/1.png' \/><\/center>K\u1ebft qu\u1ea3 c\u1ee7a ph\u00e9p nh\u00e2n $\\left( 4{{x}^{3}}-5x+2{{x}^{8}} \\right)\\left( -{{x}^{5}} \\right)$ l\u00e0 \u0111a th\u1ee9c b\u1eadc $8$ <b> \u0111\u00fang <\/b> hay <b> sai <\/b>? ","select":["\u0110\u00fang","Sai"],"hint":"Ta nh\u00e2n \u0111\u01a1n th\u1ee9c v\u1edbi \u0111a th\u1ee9c, s\u1eed d\u1ee5ng c\u00f4ng th\u1ee9c: $a.(b+c)=a.b+a.c$<br\/> B\u1eadc c\u1ee7a \u0111a th\u1ee9c m\u1ed9t bi\u1ebfn l\u00e0 s\u1ed1 m\u0169 cao nh\u1ea5t c\u1ee7a bi\u1ebfn.","explain":"<span class='basic_left'>Ta th\u1ef1c hi\u1ec7n ph\u00e9p nh\u00e2n:<br\/>$\\left( 4{{x}^{3}}-5x+2{{x}^{8}} \\right)\\left( -{{x}^{5}} \\right) \\\\ =-4{{x}^{8}}+5{{x}^{6}}-2{{x}^{13}} \\\\=-2{{x}^{13}}-4{{x}^{8}}+5{{x}^{6}}$<br\/>B\u1eadc c\u1ee7a \u0111a th\u1ee9c l\u00e0 $13$. <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 Sai.<\/span>","column":2}]}],"id_ques":302},{"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":[[["2"],["0"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"\u0110i\u1ec1n v\u00e0o c\u00e1c \u00f4 tr\u1ed1ng trong b\u00e0i gi\u1ea3i t\u00ecm $x$ sau:<br\/>$\\begin{align} & x\\left( x-{{x}^{2}} \\right)+x\\left( x+{{x}^{2}} \\right)=0 \\\\ & \\Leftrightarrow {{x}^{2}}-{{x}^{3}}+{{x}^{2}}+{{x}^{3}}=0 \\\\ &\\Leftrightarrow \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}{{x}^{2}}=0 \\\\ &\\Leftrightarrow x= \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}\\\\ \\end{align}$","hint":"Ta r\u00fat g\u1ecdn b\u1eb1ng c\u00e1ch c\u1ed9ng (tr\u1eeb) c\u00e1c \u0111\u01a1n th\u1ee9c \u0111\u1ed3ng d\u1ea1ng v\u1edbi nhau.","explain":"<span class='basic_left'>Ta tr\u00ecnh b\u00e0y m\u1ed9t b\u00e0i gi\u1ea3i ho\u00e0n ch\u1ec9nh nh\u01b0 sau:<br\/>$\\begin{align} & x\\left( x-{{x}^{2}} \\right)+x\\left( x+{{x}^{2}} \\right)=0 \\\\ &\\Leftrightarrow {{x}^{2}}-{{x}^{3}}+{{x}^{2}}+{{x}^{3}}=0 \\\\ &\\Leftrightarrow 2{{x}^{2}}=0 \\\\ &\\Leftrightarrow x^2=0 \\\\ &\\Leftrightarrow x=0 \\\\ \\end{align}$<br\/><span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n v\u00e0o hai \u00f4 l\u00e0 $2$ v\u00e0 $0$.<\/span>"}]}],"id_ques":303},{"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":[[["0"]]],"list":[{"point":5,"width":40,"content":"","type_input":"","ques":"<span class='basic_left'>T\u00ecm $x$, bi\u1ebft: $\\dfrac{1}{2}x\\left( {{x}^{2}}-3 \\right)=4x+\\dfrac{1}{2}{{x}^{3}}$. <br\/> Gi\u00e1 tr\u1ecb c\u1ee7a $x$ c\u1ea7n t\u00ecm l\u00e0 _input_ <\/span>","hint":"T\u1eeb gi\u1ea3 thi\u1ebft, ta bi\u1ebfn \u0111\u1ed5i \u0111\u1eb3ng th\u1ee9c \u0111\u1ec3 t\u00ecm $x$.<br\/>S\u1eed d\u1ee5ng c\u00f4ng th\u1ee9c nh\u00e2n \u0111\u01a1n th\u1ee9c v\u1edbi \u0111a th\u1ee9c: $a(b+c)=a.b+a.c$","explain":"<span class='basic_left'> Ta c\u00f3:<br\/>$ \\dfrac{1}{2}x\\left( {{x}^{2}}-3 \\right)=4x+\\dfrac{1}{2}{{x}^{3}} \\\\ \\Leftrightarrow \\dfrac{1}{2}{{x}^{3}}-\\frac{3}{2}x=4x+\\dfrac{1}{2}{{x}^{3}} \\\\ \\Leftrightarrow -\\dfrac{3}{2}x=4x \\\\ \\Leftrightarrow -\\dfrac{3}{2}x-4x=0 \\\\ \\Leftrightarrow \\dfrac{-11}{2}x=0 \\\\ \\Leftrightarrow x=0 $<br\/> <span class='basic_pink'> V\u1eady gi\u00e1 tr\u1ecb $x$ c\u1ea7n \u0111i\u1ec1n l\u00e0 $0$ <\/span>"}]}],"id_ques":304},{"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":"Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c ${{y}^{5}}\\left( {{y}^{2}}-9 \\right)$ b\u1eb1ng $0$ t\u1ea1i ","select":["A. $\\left[ \\begin{align}& y=0 \\\\ & y=3 \\\\ & y=-3 \\\\ \\end{align} \\right.$","B. $\\left[ \\begin{align}& y=1 \\\\ & y=3 \\\\ \\end{align} \\right.$","C. $\\left[ \\begin{align}& y=1 \\\\ & y=3 \\\\ & y=-3 \\\\ \\end{align} \\right.$","D. $\\left[ \\begin{align}& y=1 \\\\ & y=2 \\\\ & y=-3 \\\\ \\end{align} \\right.$"],"hint":"N\u1ebfu $a.b = 0$ th\u00ec ho\u1eb7c $a = 0$ ho\u1eb7c $b = 0$","explain":"<span class='basic_left'>T\u1eeb bi\u1ec3u th\u1ee9c \u0111\u1ea7u b\u00e0i ta c\u00f3: <br\/>${{y}^{5}}\\left( {{y}^{2}}-9 \\right)=0\\Rightarrow \\left[ \\begin{aligned}& {{y}^{5}}=0 \\\\ & {{y}^{2}}-9=0 \\\\ \\end{aligned} \\right.\\Leftrightarrow \\left[ \\begin{aligned}& y=0 \\\\ & {{y}^{2}}=9 \\\\ \\end{aligned} \\right.\\Rightarrow \\left[ \\begin{aligned} & y=0 \\\\ & y=3 \\\\ & y=-3 \\\\ \\end{aligned} \\right.$<br\/><span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span>","column":2}]}],"id_ques":305},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o ch\u1ed7 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["6"],["5"]]],"list":[{"point":5,"width":50,"type_input":"","ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop8/toan/daiso/bai1/lv2/img\/1.png' \/><\/center>H\u1ec7 s\u1ed1 cao nh\u1ea5t c\u1ee7a \u0111a th\u1ee9c $\\left( {{x}^{8}}-\\dfrac{1}{2}{{x}^{3}}+x \\right)\\left( -\\dfrac{6}{5}x \\right)$ l\u00e0: $-\\dfrac{\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}}{\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}}$","hint":"Trong \u0111a th\u1ee9c m\u1ed9t bi\u1ebfn: H\u1ec7 s\u1ed1 cao nh\u1ea5t l\u00e0 h\u1ec7 s\u1ed1 \u0111i v\u1edbi l\u0169y th\u1eeba b\u1eadc cao nh\u1ea5t c\u1ee7a bi\u1ebfn","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn<\/span><br\/> Nh\u00e2n \u0111\u01a1n th\u1ee9c v\u1edbi \u0111a th\u1ee9c.<br\/> S\u1eafp x\u1ebfp \u0111a th\u1ee9c theo l\u0169y th\u1eeba gi\u1ea3m d\u1ea7n v\u00e0 t\u00ecm h\u1ec7 s\u1ed1 \u0111i v\u1edbi l\u0169y th\u1eeba c\u00f3 b\u1eadc cao nh\u1ea5t c\u1ee7a bi\u1ebfn.<br\/><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> Ta c\u00f3:<br\/>$\\left( {{x}^{8}}-\\dfrac{1}{2}{{x}^{3}}+x \\right)\\left( -\\dfrac{6}{5}x \\right) \\\\ =-\\dfrac{6}{5}{{x}^{9}}+\\dfrac{3}{5}{{x}^{4}}-\\dfrac{6}{5}{{x}^{2}}$<br\/> \u0110a th\u1ee9c c\u00f3 l\u0169y th\u1eeba b\u1eadc cao nh\u1ea5t c\u1ee7a bi\u1ebfn l\u00e0 $x^9$ <br\/> H\u1ec7 s\u1ed1 \u0111i v\u1edbi $x^9$ l\u00e0 $\\dfrac{-6}{5}$.<br\/> Do \u0111\u00f3 h\u1ec7 s\u1ed1 cao nh\u1ea5t l\u00e0 $\\dfrac{-6}{5}$<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n l\u00e0 $6$ v\u00e0 $5$<\/span> "}]}],"id_ques":306},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o ch\u1ed7 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/bai1/lv2/img\/1.png' \/><\/center>H\u1ec7 s\u1ed1 cao nh\u1ea5t c\u1ee7a \u0111a th\u1ee9c $\\dfrac{4}{3}{{x}^{2}}\\left( 7-\\dfrac{3}{2}{{x}^{3}}+15x \\right)$ l\u00e0 _input_","hint":"Trong \u0111a th\u1ee9c m\u1ed9t bi\u1ebfn: H\u1ec7 s\u1ed1 cao nh\u1ea5t l\u00e0 h\u1ec7 s\u1ed1 \u0111i v\u1edbi l\u0169y th\u1eeba b\u1eadc cao nh\u1ea5t c\u1ee7a bi\u1ebfn","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn<\/span><br\/> Nh\u00e2n \u0111\u01a1n th\u1ee9c v\u1edbi \u0111a th\u1ee9c.<br\/> S\u1eafp x\u1ebfp \u0111a th\u1ee9c theo l\u0169y th\u1eeba gi\u1ea3m d\u1ea7n v\u00e0 t\u00ecm h\u1ec7 s\u1ed1 \u0111i v\u1edbi l\u0169y th\u1eeba c\u1ee7a bi\u1ebfn c\u00f3 b\u1eadc cao nh\u1ea5t. <br\/><span class='basic_green'>Gi\u1ea3i<\/span><br\/>Ta c\u00f3:<br\/>$\\dfrac{4}{3}{{x}^{2}}\\left( 7-\\dfrac{3}{2}{{x}^{3}}+15x \\right) \\\\ =\\dfrac{28}{3}{{x}^{2}}-2{{x}^{5}}+20{{x}^{3}} \\\\=-2{{x}^{5}}+20{{x}^{3}}+\\dfrac{28}{3}{{x}^{2}}$<br\/> \u0110a th\u1ee9c c\u00f3 l\u0169y th\u1eeba cao nh\u1ea5t c\u1ee7a bi\u1ebfn l\u00e0 $x^5$ <br\/> H\u1ec7 s\u1ed1 \u0111i v\u1edbi $x^5$ l\u00e0 $-2$.<br\/> Do \u0111\u00f3 h\u1ec7 s\u1ed1 cao nh\u1ea5t l\u00e0 $- 2$.<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n l\u00e0 $-2$.<\/span> "}]}],"id_ques":307},{"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":"Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c $\\dfrac{5}{3}{{x}^{3}}\\left( x+\\dfrac{1}{5}{{x}^{2}}-1 \\right)$ t\u1ea1i $x = 3$ l\u00e0 ","select":["A. 169","B. 150","C. 171","D. 170"],"hint":"Thay gi\u00e1 tr\u1ecb $x = 3$ v\u00e0o bi\u1ec3u th\u1ee9c.","explain":"<span class='basic_left'>V\u1edbi $x = 3$ ta c\u00f3:<br\/>$\\dfrac{5}{3}{{x}^{3}}\\left( x+\\dfrac{1}{5}{{x}^{2}}-1 \\right)=\\dfrac{5}{3}{{.3}^{3}}\\left( 3+\\dfrac{1}{5}{{.3}^{2}}-1 \\right)=171$ <br\/><span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span>","column":2}]}],"id_ques":308},{"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":"Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c $5x{{y}^{2}}\\left( \\dfrac{1}{5}-x+y \\right)$ t\u1ea1i $x = 1; y = 2$ l\u00e0 ","select":["A. 26","B. 24","C. 50","D. 30"],"hint":"Thay $x = 1; y = 2$ v\u00e0o bi\u1ec3u th\u1ee9c \u0111\u00e3 cho r\u1ed3i t\u00ednh.","explain":"<span class='basic_left'>V\u1edbi $x = 1;y=2$ ta c\u00f3:<br\/>$5x{{y}^{2}}\\left( \\dfrac{1}{5}-x+y \\right)={{5.1.2}^{2}}\\left( \\dfrac{1}{5}-1+2 \\right)=20.\\dfrac{6}{5}=24$ <br\/><span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span>","column":2}]}],"id_ques":309},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o ch\u1ed7 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["46"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c $\\left( xy-3{{y}^{2}}+\\dfrac{1}{2} \\right)\\left( -2y \\right)$ t\u1ea1i $x = 0; y = 2$ l\u00e0_input_","hint":"Thay gi\u00e1 tr\u1ecb $x = 0; y = 2$ v\u00e0o bi\u1ec3u th\u1ee9c r\u1ed3i t\u00ednh.","explain":"<<span class='basic_left'>V\u1edbi $x = 0; y = 2$ ta c\u00f3:<br\/>$\\left( xy-3{{y}^{2}}+\\dfrac{1}{2} \\right)\\left( -2y \\right)=\\left( 0.2-{{3.2}^{2}}+\\dfrac{1}{2} \\right)\\left( -2.2 \\right)=46$ <br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n l\u00e0 $46$.<\/span> "}]}],"id_ques":310},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o ch\u1ed7 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["1"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c $xy\\left( 2{{x}^{2}}-y \\right)$ t\u1ea1i $x = y = 1$ l\u00e0_input_","hint":"Thay gi\u00e1 tr\u1ecb $x = y = 1$ v\u00e0o bi\u1ec3u th\u1ee9c r\u1ed3i t\u00ednh.","explain":"<span class='basic_left'>V\u1edbi $x = y = 1$ ta c\u00f3:<br\/>$xy\\left( 2{{x}^{2}}-y \\right)=1.1\\left( {{2.1}^{2}}-1 \\right)=1$ <br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n l\u00e0 $1$.<\/span> "}]}],"id_ques":311},{"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":[[["0"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"Gi\u00e1 tr\u1ecb bi\u1ec3u th\u1ee9c $2{{x}^{3}}y\\left( \\dfrac{3}{2}x+1 \\right)$ t\u1ea1i $x = 2; y = 0$ l\u00e0 _input_","hint":"Thay gi\u00e1 tr\u1ecb $x = 2; y = 0$ v\u00e0o bi\u1ec3u th\u1ee9c r\u1ed3i t\u00ednh.","explain":"<span class='basic_left'>V\u1edbi $x = 2; y = 0$ ta c\u00f3:<br\/>$2{{x}^{3}}y\\left( \\dfrac{3}{2}x+1 \\right)={{2.2}^{3}}.0\\left( \\dfrac{3}{2}.2+1 \\right)=0$<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n l\u00e0 $0$.<\/span>"}]}],"id_ques":312},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng \u0111\u1ec3 \u0111\u01b0\u1ee3c m\u1ed9t khai tri\u1ec3n \u0111\u00fang ","title_trans":"","temp":"fill_the_blank","correct":[[["xyz"]]],"list":[{"point":5,"width":50,"type_input":"","ques":"${{y}^{3}}\\left(\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} +{{y}^{2}}z-6 \\right)$$=x{{y}^{4}}z+{{y}^{5}}z-6{{y}^{3}}$","hint":"\u0110\u00e2y l\u00e0 ph\u00e9p nh\u00e2n \u0111\u01a1n th\u1ee9c v\u1edbi \u0111a th\u1ee9c.<br\/>Nh\u1eadn \u0111\u1ecbnh t\u1eeb v\u1ebf ph\u1ea3i c\u1ee7a \u0111\u1eb3ng th\u1ee9c \u0111\u00e3 cho \u0111\u1ec3 \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng sao cho \u0111\u00fang nh\u1ea5t.","explain":"<span class='basic_left'> Nh\u00ecn v\u00e0o v\u1ebf ph\u1ea3i c\u1ee7a \u0111\u1eb3ng th\u1ee9c \u0111\u00e3 cho, ta th\u1ea5y c\u00f3 h\u1ea1ng t\u1eed $xy^4z$.<br\/> M\u00e0 $xy^4z$ l\u00e0 k\u1ebft qu\u1ea3 c\u1ee7a ph\u00e9p nh\u00e2n \u00f4 tr\u1ed1ng v\u1edbi $y^3$.<br\/>T\u1ee9c l\u00e0 $y^3\\times....=xy^4z$<br\/> Suy ra c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $xyz$.<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n l\u00e0 $xyz$.<\/span>"}]}],"id_ques":313},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng \u0111\u1ec3 \u0111\u01b0\u1ee3c m\u1ed9t khai tri\u1ec3n \u0111\u00fang ","title_trans":"","temp":"fill_the_blank","correct":[[["xy"]]],"list":[{"point":5,"width":50,"type_input":"","ques":"$\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}\\left( \\dfrac{1}{3}{{y}^{2}}+x-1 \\right)$$=\\dfrac{1}{3}x{{y}^{3}}+{{x}^{2}}y-xy$","hint":"\u0110\u00e2y l\u00e0 ph\u00e9p nh\u00e2n \u0111\u01a1n th\u1ee9c v\u1edbi \u0111a th\u1ee9c.<br\/>Nh\u1eadn \u0111\u1ecbnh t\u1eeb v\u1ebf ph\u1ea3i c\u1ee7a \u0111\u1eb3ng th\u1ee9c \u0111\u00e3 cho \u0111\u1ec3 \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng sao cho \u0111\u00fang nh\u1ea5t.","explain":"<span class='basic_left'> Nh\u00ecn v\u00e0o v\u1ebf ph\u1ea3i c\u1ee7a \u0111\u1eb3ng th\u1ee9c \u0111\u00e3 cho, ta th\u1ea5y c\u00f3 h\u1ea1ng t\u1eed $\\dfrac{1}{3}x{{y}^{3}}$.<br\/> M\u00e0 $\\dfrac{1}{3}x{{y}^{3}}$ l\u00e0 k\u1ebft qu\u1ea3 c\u1ee7a ph\u00e9p nh\u00e2n \u00f4 tr\u1ed1ng v\u1edbi $\\dfrac{1}{3}y^2$.<br\/>T\u1ee9c l\u00e0 $.....\\times \\dfrac{1}{3}y^2=\\dfrac{1}{3}xy^3$<br\/> Suy ra c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $xy$.<br\/><span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n l\u00e0 $xy$.<\/span><\/span>"}]}],"id_ques":314},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng \u0111\u1ec3 \u0111\u01b0\u1ee3c m\u1ed9t khai tri\u1ec3n \u0111\u00fang ","title_trans":"","temp":"fill_the_blank","correct":[[["x"],["y"],["2"],["y"],["3"],["z"]]],"list":[{"point":5,"width":20,"type_input":"","ques":"${{y}^{2}}\\left( x+yz \\right)$$=\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}.\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}$$+\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^\\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":"\u0110\u00e2y l\u00e0 ph\u00e9p nh\u00e2n \u0111\u01a1n th\u1ee9c v\u1edbi \u0111a th\u1ee9c, \u00e1p d\u1ee5ng: $a(b+c)=a.b+a.c$","explain":"<span class='basic_left'>Ta c\u00f3:<br\/> ${{y}^{2}}\\left( x+yz \\right)=x{{y}^{2}}+\\,{{y}^{3}}z$ <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n ho\u00e0n ch\u1ec9nh v\u00e0o c\u00e1c \u00f4 l\u1ea7n l\u01b0\u1ee3t l\u00e0 $x, y, 2, y, 3, z$<\/span><\/span> "}]}],"id_ques":315},{"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":"K\u1ebft qu\u1ea3 ph\u00e9p nh\u00e2n $-4xy\\left( 2x{{y}^{2}}-3{{x}^{2}}y \\right)$ l\u00e0: ","select":["A.$-8{{x}^{2}}{{y}^{3}}+12{{x}^{3}}{{y}^{2}}$ ","B.$-8x{{y}^{3}}+12{{x}^{3}}{{y}^{2}}$ ","C.$-8x{{y}^{3}}-12{{x}^{3}}{{y}^{2}}$","D.$-8{{x}^{2}}{{y}^{3}}-12x{{y}^{2}}$"],"hint":"\u0110\u00e2y l\u00e0 ph\u00e9p nh\u00e2n \u0111\u01a1n th\u1ee9c v\u1edbi \u0111a th\u1ee9c, \u00e1p d\u1ee5ng: $a(b+c)=a.b+a.c$","explain":"<span class='basic_left'>Ta c\u00f3:<br\/>$-4xy\\left( 2x{{y}^{2}}-3{{x}^{2}}y \\right)=-8{{x}^{2}}{{y}^{3}}+12{{x}^{3}}{{y}^{2}}$<br\/><span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span>","column":2}]}],"id_ques":316},{"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":"K\u1ebft qu\u1ea3 ph\u00e9p nh\u00e2n $\\left( -5x \\right)\\left( 3{{x}^{3}}-x \\right)$ l\u00e0: ","select":["A. $-15{{x}^{4}}-5{{x}^{2}}$ ","B. $-15{{x}^{4}}+5{{x}^{2}}$ ","C. $15{{x}^{4}}+5{{x}^{2}}$","D. $-15{{x}^{4}}-5{{x}^{3}}$"],"hint":"","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> Nh\u00e2n h\u1ea1ng t\u1eed b\u00ean ngo\u00e0i v\u1edbi t\u1eebng h\u1ea1ng t\u1eed trong \u0111a th\u1ee9c: $a(b+c) = a.b + a.c$ <br\/><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/>Ta c\u00f3:<br\/>$\\left( -5x \\right)\\left( 3{{x}^{3}}-x \\right)=-15{{x}^{4}}+5{{x}^{2}}$<\/span><br\/><span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span>","column":2}]}],"id_ques":317},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["2"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"H\u1ec7 s\u1ed1 c\u1ee7a $x^4$ trong k\u1ebft qu\u1ea3 ph\u00e9p nh\u00e2n ${{x}^{3}}\\left( 2x-\\dfrac{3}{2}+5{{x}^{4}} \\right)$ l\u00e0 _input_","hint":"\u0110\u00e2y l\u00e0 ph\u00e9p nh\u00e2n \u0111\u01a1n th\u1ee9c v\u1edbi \u0111a th\u1ee9c, \u00e1p d\u1ee5ng: $a(b+c)=a.b+a.c$<br\/> T\u00ecm h\u1ec7 s\u1ed1 \u0111i v\u1edbi $x^4$.","explain":"<span class='basic_left'>Ta c\u00f3:<br\/> ${{x}^{3}}\\left( 2x-\\dfrac{3}{2}+5{{x}^{4}} \\right) \\\\ =2{{x}^{4}}-\\dfrac{3}{2}{{x}^{3}}+5{{x}^{7}} \\\\ =5{{x}^{7}}+2{{x}^{4}}-\\dfrac{3}{2}{{x}^{3}}$<br\/> H\u1ec7 s\u1ed1 \u0111i v\u1edbi $x^4$ l\u00e0 $2$. <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n l\u00e0 $2$.<\/span><\/span> "}]}],"id_ques":318},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng ","title_trans":"","temp":"fill_the_blank","correct":[[["5"],["2"]]],"list":[{"point":5,"width":40,"type_input":"","ques":"H\u1ec7 s\u1ed1 c\u1ee7a $x^7$ trong k\u1ebft qu\u1ea3 ph\u00e9p nh\u00e2n $\\dfrac{1}{2}{{x}^{4}}\\left( x+5{{x}^{3}}-8 \\right)$ l\u00e0 $\\dfrac{\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}}{\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}}$","hint":"","explain":"<span class='basic_left'>Ta c\u00f3:<br\/> $\\dfrac{1}{2}{{x}^{4}}\\left( x+5{{x}^{3}}-8 \\right) =\\dfrac{1}{2}{{x}^{5}}+\\dfrac{5}{2}{{x}^{7}}-4{{x}^{4}}$<br\/> H\u1ec7 s\u1ed1 \u0111i v\u1edbi $x^7$ l\u00e0 $\\dfrac{5}{2}$. <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n l\u00e0 $\\dfrac{5}{2}$.<\/span> "}]}],"id_ques":319},{"time":24,"part":[{"title":"\u0110i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng \u0111\u1ec3 \u0111\u01b0\u1ee3c m\u1ed9t khai tri\u1ec3n \u0111\u00fang ","title_trans":"","temp":"fill_the_blank","correct":[[["3"],["6"]]],"list":[{"point":5,"width":50,"type_input":"","ques":"$\\dfrac{3}{2}{{x}^{2}}\\left( x+2{{y}^{2}}+4 \\right)$$=\\dfrac{3}{2}{{x}^{3}}+\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}{{x}^{2}}{{y}^{2}}$$+\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}{{x}^{2}}$","hint":"","explain":"<span class='basic_left'>Ta th\u1ef1c hi\u1ec7n ph\u00e9p nh\u00e2n:<br\/> $\\dfrac{3}{2}{{x}^{2}}\\left( x+2{{y}^{2}}+4 \\right)=\\dfrac{3}{2}{{x}^{3}}+3{{x}^{2}}{{y}^{2}}+6{{x}^{2}}$ <br\/> <span class='basic_pink'>V\u1eady \u0111\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n ho\u00e0n ch\u1ec9nh l\u00e0 $3$ v\u00e0 $6$.<\/span> "}]}],"id_ques":320}],"lesson":{"save":0,"level":2}}