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{"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"]]],"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 = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}\\dfrac{2}{7} $ (nh\u1eadp ph\u1ea7n nguy\u00ean c\u1ee7a h\u1ed7n s\u1ed1.)","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 $17\\dfrac{2}{7}.$ <br\/> <span class='basic_pink'> V\u1eady ph\u1ea7n nguy\u00ean c\u1ea7n \u0111i\u1ec1n l\u00e0 $17$ <\/span><\/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 = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} $ ","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='http://dev.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='http://dev.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} \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} \\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='http://dev.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai5/lv2/img\/10.jpg'\/><\/center> So s\u00e1nh hai l\u0169y th\u1eeba sau: $ 2^{91} \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} 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='http://dev.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='http://dev.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='http://dev.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}} = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} $ ","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='http://dev.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai5/lv2/img\/4.jpg'\/><\/center> $ B = \\dfrac{5^{4}.20^{4}}{25^{5}.4^{5}}= \\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":"$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='http://dev.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)^{\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}} $","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='http://dev.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='http://dev.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='http://dev.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='http://dev.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='http://dev.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) = \\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":"\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}}

Điểm của bạn.

Câu hỏi này theo dạng chọn đáp án đúng, sau khi đọc xong câu hỏi, bạn bấm vào một trong số các đáp án mà chương trình đưa ra bên dưới, sau đó bấm vào nút gửi để kiểm tra đáp án và sẵn sàng chuyển sang câu hỏi kế tiếp

Trả lời đúng trong khoảng thời gian quy định bạn sẽ được + số điểm như sau:
Trong khoảng 1 phút đầu tiên + 5 điểm
Trong khoảng 1 phút -> 2 phút + 4 điểm
Trong khoảng 2 phút -> 3 phút + 3 điểm
Trong khoảng 3 phút -> 4 phút + 2 điểm
Trong khoảng 4 phút -> 5 phút + 1 điểm

Quá 5 phút: không được cộng điểm

Tổng thời gian làm mỗi câu (không giới hạn)

Điểm của bạn.

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