{"segment":[{"time":24,"part":[{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["4"],["1"],["0"],["1"],["4"]]],"list":[{"point":5,"width":50,"type_input":"","ques":"<table><tr><td>a<\/td><td>-2<\/td><td>-1<\/td><td>0<\/td><td>1<\/td><td>2<\/td><\/tr><tr><td>$a^{2}$<\/td><td>_input_<\/td><td>_input_<\/td><td>_input_<\/td><td>_input_<\/td><td>_input_<\/td><\/tr><\/table>","explain":" Thay l\u1ea7n l\u01b0\u1ee3t gi\u00e1 tr\u1ecb c\u1ee7a $a$ v\u00e0o $a^{2}$ <br\/> V\u1edbi $a = -2 $ th\u00ec $ (-2)^{2} = 4$ <br\/>V\u1edbi $a = -1 $ th\u00ec $ (-1)^{2} = 1$ <br\/> V\u1edbi $a = 0 $ th\u00ec $ (0)^{2} = 0$ <br\/> V\u1edbi $a = 1 $ th\u00ec $ (1)^{2} = 1$ <br\/> V\u1edbi $a = 2 $ th\u00ec $ (2)^{2} = 4$ <br\/> <br\/> <span class='basic_pink'> Gi\u00e1 tr\u1ecb c\u1ea7n \u0111i\u1ec1n l\u1ea7n l\u01b0\u1ee3t l\u00e0 $4; 1; 0; 1; 4$.<\/span><\/span> <span class='basic_left'> <i> L\u01b0u \u00fd: <\/i> $\\bullet$ L\u0169y th\u1eeba b\u1eadc ch\u1eb5n c\u1ee7a m\u1ed9t s\u1ed1 \u00e2m l\u00e0 m\u1ed9t s\u1ed1 d\u01b0\u01a1ng. <br\/> $\\qquad \\quad \\bullet$ L\u0169y th\u1eeba c\u1ee7a m\u1ed9t s\u1ed1 d\u01b0\u01a1ng l\u00e0 m\u1ed9t s\u1ed1 d\u01b0\u01a1ng. <\/span> <br\/> "}]}],"id_ques":221},{"time":24,"part":[{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["-8"],["-1"],["0"],["1"],["8"]]],"list":[{"point":5,"width":50,"type_input":"","ques":"<table><tr><td>a<\/td><td>-2<\/td><td>-1<\/td><td>0<\/td><td>1<\/td><td>2<\/td><\/tr><tr><td>$a^{3}$<\/td><td>_input_<\/td><td>_input_<\/td><td>_input_<\/td><td>_input_<\/td><td>_input_<\/td><\/tr><\/table>","explain":"Thay l\u1ea7n l\u01b0\u1ee3t gi\u00e1 tr\u1ecb c\u1ee7a $a$ v\u00e0o $a^{3}$ <br\/> V\u1edbi $a = -2 $ th\u00ec $ (-2)^{3} = -8$ <br\/> V\u1edbi $a = -1 $ th\u00ec $ (-1)^{3} = -1$ <br\/> V\u1edbi $a = 0 $ th\u00ec $ 0^{3} = 0$ <br\/> V\u1edbi $a = 1 $ th\u00ec $ 1^{3} = 1$ <br\/> V\u1edbi $a = 2 $ th\u00ec $ 2^{3} = 8$ <br\/> <br\/> <span class='basic_pink'> Gi\u00e1 tr\u1ecb c\u1ea7n \u0111i\u1ec1n l\u00e0 $-8; -1 ; 0; 1; 8$.<\/span><\/span> <span class='basic_left'> <i> L\u01b0u \u00fd: <\/i> L\u0169y th\u1eeba b\u1eadc l\u1ebb c\u1ee7a m\u1ed9t s\u1ed1 \u00e2m l\u00e0 m\u1ed9t s\u1ed1 \u00e2m. <\/span> <br\/>"}]}],"id_ques":222},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00fang hay sai","title_trans":"M\u1ed7i \u0111\u1eb3ng th\u1ee9c sau c\u00f3 \u0111\u00fang v\u1edbi m\u1ecdi s\u1ed1 h\u1eefu t\u1ec9 x v\u00e0 y hay kh\u00f4ng?","temp":"true_false","correct":[["f","t","t","f"]],"content":"","list":[{"point":5,"image":"","col_name":["","\u0110\u00fang","Sai"],"arr_ques":[" $ -x^{4} = (-x)^{4} $ "," $ -x^{3} = (-x)^{3} $ "," $ (-x)^{2} = x^{2} $ ","$ (-x)^{5} = x^{5} $"],"hint":" <br\/> $\\bullet$ L\u0169y th\u1eeba b\u1eadc ch\u1eb5n c\u1ee7a m\u1ed9t s\u1ed1 \u00e2m l\u00e0 m\u1ed9t s\u1ed1 d\u01b0\u01a1ng. <br\/> $ \\bullet$ L\u0169y th\u1eeba b\u1eadc l\u1ebb c\u1ee7a m\u1ed9t s\u1ed1 \u00e2m l\u00e0 m\u1ed9t s\u1ed1 \u00e2m.","explain":[" Do L\u0169y th\u1eeba b\u1eadc ch\u1eb5n c\u1ee7a m\u1ed9t s\u1ed1 \u00e2m l\u00e0 m\u1ed9t s\u1ed1 d\u01b0\u01a1ng n\u00ean $ -x^{4} = (-x)^{4} $ (Sai). \u0110\u1eb3ng th\u1ee9c \u0111\u00fang khi $x = 0 $ ","<br\/> Do L\u0169y th\u1eeba b\u1eadc l\u1ebb c\u1ee7a m\u1ed9t s\u1ed1 \u00e2m l\u00e0 m\u1ed9t s\u1ed1 \u00e2m n\u00ean $ -x^{3} = (-x)^{3} $ (\u0110\u00fang) ","<br\/> Do L\u0169y th\u1eeba b\u1eadc ch\u1eb5n c\u1ee7a m\u1ed9t s\u1ed1 \u00e2m l\u00e0 m\u1ed9t s\u1ed1 d\u01b0\u01a1ng n\u00ean $ (-x)^{2} = x^{2}$ (\u0110\u00fang). ","<br\/>Do L\u0169y th\u1eeba b\u1eadc l\u1ebb c\u1ee7a m\u1ed9t s\u1ed1 \u00e2m l\u00e0 m\u1ed9t s\u1ed1 \u00e2m n\u00ean $ (-x)^{5} = x^{5} $ (Sai). \u0110\u1eb3ng th\u1ee9c \u0111\u00fang khi $x = 0 $ "]}]}],"id_ques":223},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00fang hay sai","title_trans":"","temp":"true_false","correct":[["f","t","t","f"]],"list":[{"point":5,"image":"","col_name":["","\u0110\u00fang","Sai"],"arr_ques":[" $-x = (-x)^{2}$ "," $ (x - y)^{2} = (y - x)^{2}$ "," $x < 0 \\Rightarrow x^{2} > x$ ","N\u1ebfu $x^{2} > 0 $ th\u00ec $x > 0 $"],"hint":"","explain":["$ -x = (-x)^{2}$ (Sai). V\u00ec v\u1edbi $x = 1$ th\u00ec $-x = -1 \\neq (-x)^{2} = (-1)^{2} = 1 $","<br\/> $ (x - y)^{2} = (y - x)^{2}$ (\u0110\u00fang). V\u00ec $(x - y)^{2} = [-(y - x)^{2} ] = (y - x)^{2} $ ","<br\/> $x < 0 \\Rightarrow x^{2} > x$ (\u0110\u00fang). V\u00ec $x < 0$ th\u00ec $x < 0 < x^{2}$ ","<br\/> N\u1ebfu $x^{2} > 0 $ th\u00ec $x > 0 $ (Sai). V\u00ed d\u1ee5 $ x^{2} = (-1)^{2} = 1 > 0$ nh\u01b0ng $-1 < 0$"]}]}],"id_ques":224},{"time":9,"part":[{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["17"],["2"],["7"]]],"list":[{"point":5,"width":50,"type_input":"","ques":" T\u00ecm $x$ bi\u1ebft: $ 5^{2} . 7^{3} . 11^{2} . x - 5^{2} . 7^{2} . 11^{4} = 0 $ <br\/> <br\/><b> \u0110\u00e1p s\u1ed1: <\/b> $ x $= _input_<div class=\"frac123\"><div class=\"ts\">_input_<\/div><div class=\"ms\">_input_<\/div><\/div>","hint":"\u0110\u1eb7t nh\u00e2n t\u1eed chung ra ngo\u00e0i. ","explain":"<span class='basic_left'> Ta c\u00f3: $ 5^{2} . 7^{3} . 11^{2} . x - 5^{2} . 7^{2} . 11^{4} = 0 \\\\ \\Rightarrow (5^{2} . 7^{2} . 11^{2})(7x - 11^{2}) = 0 $ <br\/> Suy ra: $ 7x - 11^{2} = 0 $ (V\u00ec $(5^{2} . 7^{2} . 11^{2}) \\neq 0$ ) <br\/> $\\Rightarrow 7x - 121 = 0 \\\\ \\Rightarrow x = \\dfrac{121}{7} = 17\\dfrac{2}{7}$<br\/> Gi\u00e1 tr\u1ecb c\u1ee7a $x$ b\u1eb1ng $17\\dfrac{2}{7}.$<\/span> "}]}],"id_ques":225},{"time":9,"part":[{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["3"]]],"list":[{"point":5,"width":50,"type_input":"","ques":" T\u00ecm s\u1ed1 t\u1ef1 nhi\u00ean $x$ bi\u1ebft: $ 4^{x} + 4^{x+3} = 4160 $ <br\/> <b> \u0110\u00e1p s\u1ed1: <\/b> $ x = $ _input_","hint":"Ph\u00e2n t\u00edch v\u1ebf tr\u00e1i b\u1eb1ng c\u00e1ch \u0111\u1eb7t nh\u00e2n t\u1eed chung.","explain":" Ta c\u00f3: $4^{x} + 4^{x+3} = 4160 \\\\ \\Rightarrow 4^{x} + 4^{x}.4^{3} = 4160 \\\\ \\Rightarrow 4^{x}(1 + 4^{3}) = 4160 \\\\ \\Rightarrow 4^{x} = 4160 : (1 + 4^{3}) \\\\ \\Rightarrow 4^{x} = 64 \\\\ \\Rightarrow 4^{x} = 4^{3} \\Rightarrow x = 3 $ <br\/> <br\/> <span class='basic_pink'> V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n l\u00e0 $3.$ <\/span><\/span> "}]}],"id_ques":226},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":" Cho bi\u1ebft $ 32 \\geq 2^{n} > 4 \\quad (n \\in \\mathbb{N}).$ T\u00ecm t\u1eadp h\u1ee3p c\u00e1c gi\u00e1 tr\u1ecb c\u1ee7a $n$. ","select":["A. $ n \\in \\lbrace 2; 3; 4; 5 \\rbrace $","B. $ n \\in \\lbrace 3; 4; 5 \\rbrace $ ","C. $ n \\in \\lbrace 4; 5 \\rbrace $","D. $ n \\in \\lbrace 3; 4 \\rbrace $"],"hint":"\u0110\u01b0a 32 v\u00e0 4 v\u1ec1 l\u0169y th\u1eeba c\u01a1 s\u1ed1 2 r\u1ed3i t\u00ecm n","explain":" Ta c\u00f3: $ 32 \\geq 2^{n} > 4 \\quad (n \\in \\mathbb{N})$ <br\/> Suy ra $ 2^{5} \\geq 2^{n} > 2^{2} $ <br\/> V\u1eady $ n \\in \\lbrace 3; 4; 5 \\rbrace $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> ","column":2}]}],"id_ques":227},{"time":9,"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/lop7/toan/daiso/bai5/lv2/img\/10.jpg'\/><\/center> T\u00ecm $n \\in \\mathbb{N}$ th\u1ecfa m\u00e3n: $ 9 . 27 \\leq 3^{n} \\leq 243$","select":["A. $ n = 6 $","B. $ n = 3 $ ","C. $ n = 4 $","D. $ n = 5 $"],"hint":"Bi\u1ebfn \u0111\u1ed5i v\u1ebf tr\u00e1i v\u00e0 v\u1ebf ph\u1ea3i v\u1ec1 l\u0169y th\u1eeda c\u01a1 s\u1ed1 3.","explain":"<span class='basic_left'> Ta c\u00f3: $9 . 27 \\leq 3^{n} \\leq 243 \\quad (n \\in \\mathbb{N})$ <br\/> Suy ra $ 3^{2} . 3^{3} \\leq 3^{n} \\leq 3^{5}\\\\ \\Rightarrow 3^{5} \\leq 3^{n} \\leq 3^{5} $ <br\/> V\u1eady $ n = 5 $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> ","column":2}]}],"id_ques":228},{"time":9,"part":[{"title":"\u0110i\u1ec1n d\u1ea5u ''='', ''>'', ''<'' v\u00e0o \u00f4 tr\u1ed1ng","temp":"fill_the_blank","correct":[[[">"]]],"list":[{"point":5,"width":50,"type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai5/lv2/img\/10.jpg'\/><\/center> So s\u00e1nh hai l\u0169y th\u1eeba sau: $ \\left(\\dfrac{1}{16}\\right)^{10} $ _input_$\\left(\\dfrac{1}{2}\\right)^{50} $ ","hint":" \u0110\u01b0a v\u1ec1 c\u00f9ng c\u01a1 s\u1ed1: $ \\left(\\dfrac{1}{16}\\right)^{10} = \\left[ \\left(\\dfrac{1}{2}\\right)^{4}\\right]^{10} $","explain":" <span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b> * So s\u00e1nh hai l\u0169y th\u1eeba<\/b> <br\/> C\u00f3 th\u1ec3 \u0111\u01b0a v\u1ec1 so s\u00e1nh hai l\u0169y th\u1eeba c\u00f9ng s\u1ed1 m\u0169 ho\u1eb7c c\u00f9ng c\u01a1 s\u1ed1. <br\/> $\\bullet$ Khi c\u01a1 s\u1ed1 $a > 1$ v\u00e0 $ m > n > 0$ th\u00ec $a^{m} > a^{n}$ <br\/> $\\bullet$ Khi $0 < a < 1$ v\u00e0 $m > n$ th\u00ec $a^{m} < a^{n}$ <\/span> <br\/><br\/><span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> <br\/> <br\/> \u0110\u01b0a v\u1ec1 hai l\u0169y th\u1eeba c\u00f3 c\u00f9ng s\u1ed1 m\u0169 r\u1ed3i so s\u00e1nh: <br\/> <br\/> Ta c\u00f3: $ \\left(\\dfrac{1}{16}\\right)^{10} = \\left[\\left(\\dfrac{1}{2}\\right)^{4}\\right]^{10} = \\left(\\dfrac{1}{2}\\right)^{40} $ <br\/> Nh\u1eadn x\u00e9t: $ 0 < \\dfrac{1}{2} < 1; 50 > 40 $ <br\/> $ \\left(\\dfrac{1}{2}\\right)^{50} < \\left(\\dfrac{1}{2}\\right)^{40} \\Rightarrow \\left(\\dfrac{1}{2}\\right)^{50} < \\left(\\dfrac{1}{16}\\right)^{10} $ <br\/> <br\/> <span class='basic_pink'> V\u1eady d\u1ea5u c\u1ea7n \u0111i\u1ec1n l\u00e0 $>$ <\/span><\/span>"}]}],"id_ques":229},{"time":9,"part":[{"title":"\u0110i\u1ec1n d\u1ea5u ''='', ''>'', ''<'' v\u00e0o \u00f4 tr\u1ed1ng","temp":"fill_the_blank","correct":[[[">"]]],"list":[{"point":5,"width":50,"type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai5/lv2/img\/10.jpg'\/><\/center> So s\u00e1nh hai l\u0169y th\u1eeba sau: $ 2^{91} $_input_$ 5^{35} $ ","hint":"S\u1eed d\u1ee5ng t\u00ednh ch\u1ea5t b\u1eafc c\u1ea7u $a > b > c>d \\Rightarrow a > d$","explain":" <span class='basic_left'> V\u1eadn d\u1ee5ng t\u00ednh ch\u1ea5t b\u1eafc c\u1ea7u ta c\u00f3: <br\/> $5^{35} < 5^{36} \\Rightarrow 5^{35} < (5^2)^{18} = 25^{18} $ <br\/> $2^{91} > 2^{90} \\Rightarrow 2^{91} > (2^5)^{18} = 32^{18}$ <br\/> M\u00e0 $32^{18} > 25^{18} $ n\u00ean $2^{91} > 32^{18} > 25^{18 }> 5^{35}$ <br\/> Suy ra $2^{91} > 5^{35} $ <br\/> <br\/> <span class='basic_pink'> V\u1eady d\u1ea5u c\u1ea7n \u0111i\u1ec1n l\u00e0 $>$ <\/span><\/span> <br\/> "}]}],"id_ques":230},{"time":9,"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/lop7/toan/daiso/bai5/lv2/img\/4.jpg'\/><\/center> R\u00fat g\u1ecdn bi\u1ec3u th\u1ee9c $ A = \\left(\\dfrac{3}{5}\\right)^{15} : \\left(\\dfrac{9}{25}\\right)^{5} $ \u0111\u01b0\u1ee3c k\u1ebft qu\u1ea3 l\u00e0:","select":["A. $ \\left(\\dfrac{3}{5}\\right)^{20} $","B. $ \\left(\\dfrac{3}{5}\\right)^{25} $ ","C. $ \\left(\\dfrac{3}{5}\\right)^{10} $","D. $ \\left(\\dfrac{3}{5}\\right)^{5} $"],"hint":" \u0110\u01b0a v\u1ec1 c\u00f9ng c\u01a1 s\u1ed1 r\u1ed1i \u00e1p d\u1ee5ng quy t\u1eafc chia 2 l\u0169y th\u1eeba c\u00f9ng c\u01a1 s\u1ed1. ","explain":"Ta c\u00f3: $ A = \\left(\\dfrac{3}{5}\\right)^{15} : \\left(\\dfrac{9}{25}\\right)^{5} \\\\ = \\left(\\dfrac{3}{5}\\right)^{15} : \\left[\\left(\\dfrac{3}{5}\\right)^{2} \\right]^{5} \\\\ = \\left(\\dfrac{3}{5}\\right)^{15} : \\left(\\dfrac{3}{5}\\right)^{10} \\\\ = \\left(\\dfrac{3}{5}\\right)^{15-10} \\\\ = \\left(\\dfrac{3}{5}\\right)^{5} $ <br\/> <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span>","column":2}]}],"id_ques":231},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai5/lv2/img\/4.jpg'\/><\/center> K\u1ebft qu\u1ea3 c\u1ee7a bi\u1ec3u th\u1ee9c $ A = \\dfrac{(0,9)^{5}}{(0,3)^{6}} $ l\u00e0:","select":["A. $ (0,3)^{4}$","B. $ 10 $ ","C. $ 810$","D. $ 243 $"],"hint":"T\u00e1ch 0,9 = 3.0,3 r\u1ed3i \u00e1p d\u1ee5ng quy t\u1eafc l\u0169y th\u1eeba c\u1ee7a 1 t\u00edch v\u00e0 th\u01b0\u01a1ng hai l\u0169y th\u1eeba. ","explain":" Ta c\u00f3: $ A = \\dfrac{(0,9)^{5}}{(0,3)^{6}} = \\dfrac{(3.0,3)^{5}}{(0,3)^{6}} \\\\ = \\dfrac{3^{5}.(0,3)^{5}}{(0,3)^{6}} = \\dfrac{3^{5}}{0,3} \\\\ = \\dfrac{243}{0,3} = 810 $ <br\/> <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span>","column":2}]}],"id_ques":232},{"time":9,"part":[{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["1"]]],"list":[{"point":5,"width":50,"type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai5/lv2/img\/4.jpg'\/><\/center> Gi\u00e1 tr\u1ecb c\u1ee7a $ B = \\dfrac{4^{2}.4^{3}}{2^{10}} = $_input_ ","hint":"\u0110\u01b0a v\u1ec1 c\u00e1c l\u0169y th\u1eeda c\u00f3 c\u00f9ng c\u01a1 s\u1ed1 r\u1ed3i \u00e1p d\u1ee5ng quy t\u1eafc th\u01b0\u01a1ng c\u1ee7a 2 l\u0169y th\u1eeba.","explain":" Ta c\u00f3: $ B = \\dfrac{4^{2}.4^{3}}{2^{10}} = \\dfrac{4^{2+3}}{2^{2.5}} = \\dfrac{4^{5}}{4^{5}} = 1 $ <br\/> <br\/> <span class='basic_pink'> V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n l\u00e0 $1$. <\/span><\/span>"}]}],"id_ques":233},{"time":9,"part":[{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["1"],["100"]]],"list":[{"point":5,"width":50,"type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai5/lv2/img\/4.jpg'\/><\/center> $ B = \\dfrac{5^{4}.20^{4}}{25^{5}.4^{5}}$= <div class=\"frac123\"><div class=\"ts\">_input_<\/div><div class=\"ms\">_input_<\/div><\/div>","hint":"$B = \\dfrac{5^{4}.20^{4}}{25^{5}.4^{5}} = \\dfrac{5^{4}.(4.5)^{4}}{(5^{2})^{5}.4^{5}} $","explain":" Ta c\u00f3: $ B = \\dfrac{5^{4}.20^{4}}{25^{5}.4^{5}} \\\\ = \\dfrac{5^{4}.(4.5)^{4}}{(5^{2})^{5}.4^{5}} \\\\ = \\dfrac{5^{4}.5^{4}.4^{4}}{5^{10}.4^{5}} \\\\ = \\dfrac{5^{8}}{5^{10}.4 }\\\\ = \\dfrac{1}{5^{2}.4} = \\dfrac{1}{100} $ <br\/> <br\/> <span class='basic_pink'> V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n l\u1ea7n l\u01b0\u1ee3t l\u00e0 $1$ v\u00e0 $100$<\/span><\/span>"}]}],"id_ques":234},{"time":9,"part":[{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["5"]]],"list":[{"point":5,"width":50,"type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai5/lv2/img\/2.jpg'\/><\/center> K\u1ebft qu\u1ea3 c\u1ee7a ph\u00e9p chia $ \\left(\\dfrac{2}{3}\\right)^{15} : \\left(\\dfrac{4}{9}\\right)^{5} = \\left(\\dfrac{2}{3}\\right)^k$. T\u00ednh $k$ = _input_ ","hint":"\u0110\u01b0a $\\dfrac{4}{9} $ v\u1ec1 l\u0169y th\u1eeba c\u01a1 s\u1ed1 $\\dfrac{2}{3} $ r\u1ed3i th\u1ef1c hi\u1ec7n chia hai l\u0169y th\u1eeba c\u00f9ng c\u01a1 s\u1ed1 \u1edf v\u1ebf tr\u00e1i.","explain":" \u0110\u01b0a v\u1ec1 hai l\u0169y th\u1eeba c\u00f9ng c\u01a1 s\u1ed1: <br\/> $ \\left(\\dfrac{2}{3}\\right)^{15} : \\left(\\dfrac{4}{9}\\right)^{5} \\\\ = \\left(\\dfrac{2}{3}\\right)^{15} : \\left[\\left(\\dfrac{2}{3}\\right)^{2}\\right]^{5} \\\\ = \\left(\\dfrac{2}{3}\\right)^{15} : \\left(\\dfrac{2}{3}\\right)^{10} \\\\ = \\left(\\dfrac{2}{3}\\right)^{15-10} = \\left(\\dfrac{2}{3}\\right)^{5} $ <br\/> <br\/> <span class='basic_pink'> V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n l\u00e0 $5$ <\/span> <br\/>"}]}],"id_ques":235},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai5/lv2/img\/2.jpg'\/><\/center> T\u00ednh gi\u00e1 tr\u1ecb bi\u1ec3u th\u1ee9c $ \\left(\\dfrac{-10}{3}\\right)^{5} . \\left(\\dfrac{-6}{5}\\right)^{4} $ b\u1eb1ng?","select":["A. $\\dfrac{(2)^{9}.5}{3}$","B. $ \\dfrac{(-2)^{9}.3}{5}$ ","C. $ \\dfrac{(-2)^{9}.5}{3}$","D. $ \\dfrac{-853}{3} $"],"hint":" Ph\u00e2n t\u00edch ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 r\u1ed3i \u00e1p d\u1ee5ng c\u00e1c c\u00f4ng th\u1ee9c l\u0169y th\u1eeba \u0111\u1ec3 t\u00ednh to\u00e1n","explain":" Ta c\u00f3: $ \\left(\\dfrac{-10}{3}\\right)^{5} . \\left(\\dfrac{-6}{5}\\right)^{4} \\\\ = \\dfrac{(-10)^{5}}{3^{5}} . \\dfrac{(-6)^{4}}{5^{4}} \\\\ = \\dfrac{[(-2).5]^{5}}{3^{5}} . \\dfrac{[(-2).3]^{4}}{5^{4}} \\\\ = \\dfrac{(-2)^{5}.(5)^{5}.(-2)^{4}.(3)^{4}}{(3)^{5}.(5)^{4}} \\\\ = \\dfrac{(-2)^{5}.5.(-2)^{4}}{3} \\\\ = \\dfrac{(-2)^{9}.5}{3} $ <br\/> <br\/> <span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> ","column":2}]}],"id_ques":236},{"time":9,"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/lop7/toan/daiso/bai5/lv2/img\/2.jpg'\/><\/center> Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c $ \\left(\\dfrac{4}{9} + \\dfrac{1}{3}\\right)^{2} $ l\u00e0:","select":["A. $\\dfrac{49}{81}$","B. $ \\dfrac{7}{9}$ ","C. $ \\dfrac{5}{27} $","D. $ \\dfrac{169}{81} $"],"hint":" Th\u1ef1c hi\u1ec7n trong ngo\u1eb7c tr\u01b0\u1edbc r\u1ed3i \u00e1p d\u1ee5ng c\u00f4ng th\u1ee9c l\u0169y th\u1eeba c\u1ee7a m\u1ed9t s\u1ed1 h\u1eefu t\u1ec9 \u0111\u1ec3 t\u00ecm k\u1ebft qu\u1ea3","explain":" Ta c\u00f3: $ \\left(\\dfrac{4}{9} + \\dfrac{1}{3}\\right)^{2} = \\left(\\dfrac{7}{9}\\right)^{2} = \\dfrac{49}{81} $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> ","column":2}]}],"id_ques":237},{"time":9,"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/lop7/toan/daiso/bai5/lv2/img\/2.jpg'\/><\/center> Gi\u00e1 tr\u1ecb c\u1ee7a ph\u00e9p t\u00ednh $2^{2} . 2^{4} . 2^{3} $ l\u00e0: ","select":["A. $ 2^{9} $","B. $ 4^{9} $ ","C. $ 8^{9} $","D. $ 8^{24} $"],"explain":" Ta c\u00f3: $2^{2} . 2^{4} . 2^{3} = 2^{2+4+3} = 2^{9} $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> ","column":2}]}],"id_ques":238},{"time":9,"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/lop7/toan/daiso/bai5/lv2/img\/2.jpg'\/><\/center> Gi\u00e1 tr\u1ecb c\u1ee7a ph\u00e9p t\u00ednh $a^{n} . a^{2} $ l\u00e0:","select":["A. $ a^{n-2} $","B. $ (2a)^{n+2} $ ","C. $ (a.a)^{2n} $","D. $ a^{n+2} $"],"hint":"\u00c1p d\u1ee5ng c\u00f4ng th\u1ee9c: $ x^{m} . x^{n} = x^{m+n}$","explain":" Ta c\u00f3: $a^{n} . a^{2} = a^{n+2} $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> ","column":2}]}],"id_ques":239},{"time":9,"part":[{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["1"],["729"]]],"list":[{"point":5,"width":50,"type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai5/lv2/img\/2.jpg'\/><\/center> Gi\u00e1 tr\u1ecb c\u1ee7a $ \\left(-\\dfrac{1}{3}\\right)^{3} . \\left(-\\dfrac{1}{3}\\right)^{2} . \\left(-\\dfrac{1}{3}\\right) $= <div class=\"frac123\"><div class=\"ts\">_input_<\/div><div class=\"ms\">_input_<\/div><\/div>","hint":"\u00c1p d\u1ee5ng c\u00f4ng th\u1ee9c: $ x^{m} . x^{n} = x^{m+n}$","explain":" Ta c\u00f3: $\\left(-\\dfrac{1}{3}\\right)^{3} . \\left(-\\dfrac{1}{3}\\right)^{2} . \\left(-\\dfrac{1}{3}\\right) \\\\ = \\left(-\\dfrac{1}{3}\\right)^{3+2+1} \\\\ = \\left(-\\dfrac{1}{3}\\right)^{6} = \\dfrac{1}{729}$ <br\/> <br\/> <span class='basic_pink'> V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n l\u1ea7n l\u01b0\u1ee3t l\u00e0 $1$ v\u00e0 $729$ <\/span> <br\/> <span class='basic_left'> <i> L\u01b0u \u00fd: <\/i> $\\bullet$ L\u0169y th\u1eeba b\u1eadc ch\u1eb5n c\u1ee7a m\u1ed9t s\u1ed1 \u00e2m l\u00e0 m\u1ed9t s\u1ed1 d\u01b0\u01a1ng. <br\/> $\\qquad \\quad \\bullet$ L\u0169y th\u1eeba b\u1eadc l\u1ebb c\u1ee7a m\u1ed9t s\u1ed1 \u00e2m l\u00e0 m\u1ed9t s\u1ed1 \u00e2m. <\/span> <br\/>"}]}],"id_ques":240}],"lesson":{"save":0,"level":2}}