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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":[[["1"]]],"list":[{"point":10,"width":50,"content":"","type_input":"","ques":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 c\u1ee7a B v\u00e0o \u00f4 tr\u1ed1ng <br\/> $ B = \\left( \\dfrac{3}{25} - 1,12 \\right) : \\dfrac{3}{7} : \\left[ \\left( 3\\dfrac{1}{2} - 3\\dfrac{2}{3} \\right) : \\dfrac{1}{14} \\right] = $ _input_","hint":" Th\u1ef1c hi\u1ec7n trong ngo\u1eb7c tr\u01b0\u1edbc ngo\u00e0i ngo\u1eb7c sau","explain":" Ta c\u00f3: $ B = \\left( \\dfrac{3}{25} - 1,12 \\right) : \\dfrac{3}{7} : \\left[ \\left( 3\\dfrac{1}{2} - 3\\dfrac{2}{3} \\right) : \\dfrac{1}{14} \\right] \\\\ = \\left( \\dfrac{3}{25} - \\dfrac{28}{25} \\right) : \\dfrac{3}{7} : \\left[ \\left( \\dfrac{7}{2} - \\dfrac{11}{3} \\right) : \\dfrac{1}{14} \\right] \\\\ = \\dfrac{-25}{25} : \\dfrac{3}{7} : \\left( \\dfrac{21-22}{6} : \\dfrac{1}{14} \\right) \\\\ = -1 . \\dfrac{7}{3} : \\left( \\dfrac{-1}{6} . 14 \\right) \\\\ = \\dfrac{-7}{3} : \\dfrac{-7}{3} \\\\ = 1 $ <br\/> <br\/> <span class='basic_pink'> Gi\u00e1 tr\u1ecb c\u1ea7n \u0111i\u1ec1n l\u00e0 $1$.<\/span><\/span> <br\/>"}]}],"id_ques":141},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":10,"ques":" T\u00ecm th\u01b0\u01a1ng trong ph\u00e9p chia s\u1ed1 h\u1eefu t\u1ec9 \u00e2m nh\u1ecf nh\u1ea5t vi\u1ebft b\u1edfi ba ch\u1eef s\u1ed1 1 cho s\u1ed1 h\u1eefu t\u1ec9 \u00e2m l\u1edbn nh\u1ea5t vi\u1ebft b\u1edfi ba ch\u1eef s\u1ed1 1 ","select":["A. $ 100 $","B. $1221$","C. $ 10 $ ","D. $ 1 $ "],"hint":" T\u00ecm s\u1ed1 h\u1eefu t\u1ec9 \u00e2m nh\u1ecf nh\u1ea5t v\u00e0 l\u1edbn nh\u1ea5t r\u1ed3i th\u1ef1c hi\u1ec7n ph\u00e9p to\u00e1n","explain":" Ta c\u00f3: S\u1ed1 h\u1eefu t\u1ec9 \u00e2m nh\u1ecf nh\u1ea5t vi\u1ebft b\u1edfi ba ch\u1eef s\u1ed1 $1$ l\u00e0 $-111$. <br> $\\qquad$ S\u1ed1 h\u1eefu t\u1ec9 \u00e2m l\u1edbn nh\u1ea5t vi\u1ebft b\u1edfi ba ch\u1eef s\u1ed1 $1$ l\u00e0 $\\dfrac{-1}{11}$ <br\/> Suy ra : $-111 : \\dfrac{-1}{11} = -111 . (-11) = 1221$ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> <br\/>","column":2}]}],"id_ques":142},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":10,"ques":" V\u1edbi gi\u00e1 tr\u1ecb n\u00e0o c\u1ee7a x th\u00ec $A = \\left( x - \\dfrac{3}{4} \\right) \\left( x + \\dfrac{1}{2} \\right)$ l\u00e0 s\u1ed1 d\u01b0\u01a1ng?","select":["A. $ \\dfrac{-1}{2} < x < \\dfrac{3}{4} $","B. $x > \\dfrac{3}{4}$","C. $x > \\dfrac{3}{4}$ ho\u1eb7c $x < - \\dfrac{1}{2}$","D. $x > \\dfrac{-1}{2} $ "],"hint":" $ab > 0$ khi hai th\u1eeba s\u1ed1 c\u00f9ng d\u1ea5u. ","explain":" Ta c\u00f3: $A = \\left( x - \\dfrac{3}{4} \\right) \\left( x + \\dfrac{1}{2} \\right) > 0 $ khi hai th\u1eeba s\u1ed1 c\u00f9ng d\u1ea5u. <br\/> Tr\u01b0\u1eddng h\u1ee3p 1: $\\left[ \\begin{array}{} x - \\dfrac{3}{4} > 0 \\\\ x + \\dfrac{1}{2} > 0 \\end{array} \\right.$ $\\Rightarrow\\left[ \\begin{array}{} x > \\dfrac{3}{4} \\\\ x > -\\dfrac{1}{2} \\end{array} \\right.$ $ \\Rightarrow x > \\dfrac{3}{4}$ <br\/> <br\/> Tr\u01b0\u1eddng h\u1ee3p 2: $\\left[ \\begin{array}{} x - \\dfrac{3}{4} < 0 \\\\ x + \\dfrac{1}{2} < 0 \\end{array} \\right.$ $\\Rightarrow \\left[ \\begin{array}{} x < \\dfrac{3}{4} \\\\ x < -\\dfrac{1}{2} \\end{array} \\right.$ $\\Rightarrow x < \\dfrac{-1}{2}$ <br\/> \u0110\u00e1p s\u1ed1: $x > \\dfrac{3}{4}$ ho\u1eb7c $x < - \\dfrac{1}{2}$ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> <br\/>","column":2}]}],"id_ques":143},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":10,"ques":" T\u00ecm $x \\in \\mathbb{Q}$ bi\u1ebft: <br\/> $ x - 128 = \\left( 4\\dfrac{20}{21} - 5 \\right) : \\left( \\dfrac{4141}{4242} - 1 \\right) : \\left( \\dfrac{636363}{646464} - 1 \\right) $ ","select":["A. $ x = 128 $","B. $ x = 0 $","C. $ x = \\dfrac{1}{128} $","D. $ x = \\dfrac{-1}{21}$ "],"hint":" Bi\u1ebfn \u0111\u1ed5i bi\u1ec3u th\u1ee9c b\u00ean ph\u1ea3i r\u1ed3i t\u00ecm x. ","explain":" Ta c\u00f3: $ x - 128 = \\left( 4\\dfrac{20}{21} - 5 \\right) : \\left( \\dfrac{4141}{4242} - 1 \\right) : \\left( \\dfrac{636363}{646464} - 1 \\right) \\\\ x - 128 = \\left( 4 + \\dfrac{20}{21} - 5 \\right) : \\left( \\dfrac{41.101}{42.101} - 1 \\right) : \\left( \\dfrac{63.10101}{64.10101} - 1 \\right)\\\\ x - 128 = \\left(\\dfrac{20}{21} - 1 \\right) : \\left( \\dfrac{41}{42} - 1 \\right) : \\left( \\dfrac{63}{64} - 1 \\right) \\\\ x - 128 = \\left( \\dfrac{20-21}{21} \\right) : \\left( \\dfrac{41-42}{42} \\right) : \\left( \\dfrac{63-64}{64} \\right) \\\\ x -128 = \\left( \\dfrac{-1}{21} \\right) : \\left( \\dfrac{-1}{42} \\right) : \\left( \\dfrac{-1}{64} \\right) \\\\ x - 128 = \\left( \\dfrac{-1}{21} \\right) . (-42) . (-64) \\\\ x - 128 = -128 \\\\ \\Rightarrow x = 0 $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> <br\/>","column":2}]}],"id_ques":144},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":10,"ques":" C\u00f3 m\u1ea5y gi\u00e1 tr\u1ecb c\u1ee7a $x \\in \\mathbb{Z}$ th\u1ecfa m\u00e3n : <br\/> $ -4\\dfrac{3}{5} . 2\\dfrac{4}{23} \\leqslant x \\leqslant -2\\dfrac{3}{5} . 1\\dfrac{6}{15} $ ","select":["A. $ 5 $","B. $ 6 $ ","C. $ 7 $","D. $ 8 $ "],"hint":" Bi\u1ebfn \u0111\u1ed5i c\u1ea3 2 v\u1ebf r\u1ed3i t\u00ecm k\u1ebft qu\u1ea3. ","explain":" Ta c\u00f3: $ -4\\dfrac{3}{5} . 2\\dfrac{4}{23} \\leqslant x \\leqslant -2\\dfrac{3}{5} . 1\\dfrac{6}{15} \\\\ \\Rightarrow \\dfrac{-23}{5} . \\dfrac{50}{23} \\leqslant x \\leqslant \\dfrac{-13}{5} . \\dfrac{21}{15} \\\\ \\Rightarrow -10 \\leqslant x \\leqslant -3\\dfrac{16}{25}$ <br\/> m\u00e0 $x \\in \\mathbb{Z}$ n\u00ean $ x \\in \\{ -10; -9; -8; -7; -6; -5; -4 \\}$ <br\/> V\u1eady c\u00f3 7 gi\u00e1 tr\u1ecb c\u1ee7a x th\u1ecfa m\u00e3n. <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> <br\/>","column":2}]}],"id_ques":145},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":10,"ques":" C\u00f3 m\u1ea5y gi\u00e1 tr\u1ecb c\u1ee7a $x \\in \\mathbb{Z}$ \u0111\u1ec3 $ F = \\dfrac{3x-2}{x+3}$ l\u00e0 s\u1ed1 nguy\u00ean?","select":["A. $ 3 $","B. $ 4 $ ","C. $ 5 $","D. $ 6 $ "],"hint":" S\u1ed1 h\u1eefu t\u1ec9 $ \\dfrac{a}{b}$ l\u00e0 s\u1ed1 nguy\u00ean khi $b$ l\u00e0 \u01b0\u1edbc c\u1ee7a $a$. ","explain":" Ta c\u00f3: $ F = \\dfrac{3x-2}{x+3} \\\\ = \\dfrac{3x+9-11}{x+3} = \\dfrac{3(x+3)-11}{x+3} = 3 - \\dfrac{11}{x+3}$<br\/> \u0110\u1ec3 $F \\in \\mathbb{Z} $ th\u00ec $\\dfrac{11}{x+3} \\in \\mathbb{Z}$ hay $(x + 3)$ l\u00e0 \u01b0\u1edbc c\u1ee7a $11$. <br\/> $\u01af(11) = ( \\pm 1; \\pm 11)$. Ta c\u00f3 b\u1ea3ng sau :<br\/> <table><tr><td>$x+3$<\/td><td>$-11$<\/td><td>$-1$<\/td><td>$1$<\/td><td>$11$<\/td><\/tr><tr><td>x<\/td><td>$-14$<\/td><td>$-4$<\/td><td>$-2$<\/td><td>$8$<\/td><\/tr><\/table> <br\/> V\u1eady c\u00f3 4 gi\u00e1 tr\u1ecb c\u1ee7a x th\u1ecfa m\u00e3n l\u00e0 $ -14; -4; -2; 8$ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> <br\/>","column":2}]}],"id_ques":146},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":10,"ques":" T\u00ecm $x \\in \\mathbb{Q}$ bi\u1ebft: <br\/> $ \\left( -0,75x + \\dfrac{5}{2} \\right) . \\dfrac{4}{7} - \\dfrac{-1}{3} = \\dfrac{-5}{6}$ ","select":["A. $ x = 6\\dfrac{1}{18}$","B. $x = \\dfrac{-109}{18}$","C. $x = -4\\dfrac{1}{2}$","D. $ x = 2\\dfrac{1}{6} $"],"hint":" \u00c1p d\u1ee5ng quy t\u1eafc nh\u00e2n, chia s\u1ed1 h\u1eefu t\u1ec9. Quy t\u1eafc chuy\u1ec3n v\u1ebf.","explain":" Ta c\u00f3: $ \\left( -0,75x + \\dfrac{5}{2} \\right) . \\dfrac{4}{7} - \\dfrac{-1}{3} = \\dfrac{-5}{6} $ <br\/> $ \\Rightarrow \\left( \\dfrac{-3}{4}x + \\dfrac{5}{2} \\right) . \\dfrac{4}{7} = \\dfrac{-5}{6} - \\dfrac{1}{3}$ <br\/> $ \\Rightarrow \\left( \\dfrac{-3}{4}x + \\dfrac{5}{2} \\right) . \\dfrac{4}{7} = \\dfrac{-7}{6} $ <br\/> $ \\Rightarrow \\dfrac{-3}{4}x + \\dfrac{5}{2} = \\dfrac{-7}{6} : \\dfrac{4}{7}$ <br\/> $ \\Rightarrow \\dfrac{-3}{4}x + \\dfrac{5}{2} = \\dfrac{-49}{24} $ <br\/> $ \\Rightarrow \\dfrac{-3}{4}x = \\dfrac{-49}{24} - \\dfrac{5}{2}$ <br\/> $ \\Rightarrow \\dfrac{-3}{4}x = \\dfrac{-109}{24}$ <br\/> $ \\Rightarrow x = \\dfrac{-109}{24} : \\dfrac{-3}{4} $ <br\/> $ \\Rightarrow x = \\dfrac{109}{18} = 6\\dfrac{1}{18}$ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> <br\/>","column":2}]}],"id_ques":147},{"time":14,"part":[{"title":"\u0110i\u1ec1n s\u1ed1 th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["3"],["13"]]],"list":[{"point":10,"width":50,"type_input":"","input_hint":["frac"],"ques":" T\u00ednh gi\u00e1 tr\u1ecb bi\u1ec3u th\u1ee9c: <br\/> $H = \\dfrac{\\dfrac{3}{4}-\\dfrac{3}{5}+\\dfrac{3}{7}+\\dfrac{3}{11}}{\\dfrac{13}{4}-\\dfrac{13}{5}+\\dfrac{13}{7}+\\dfrac{13}{11}}$ <br\/> <br\/>\u0110\u00e1p s\u1ed1: H = <div class=\"frac123\"><div class=\"ts\">_input_<\/div><div class=\"ms\">_input_<\/div><\/div>","explain":"Ta c\u00f3: $H = \\dfrac{\\dfrac{3}{4}-\\dfrac{3}{5}+\\dfrac{3}{7}+\\dfrac{3}{11}}{\\dfrac{13}{4}-\\dfrac{13}{5}+\\dfrac{13}{7}+\\dfrac{13}{11}} \\\\ = \\dfrac{3.\\left( \\dfrac{1}{4}-\\dfrac{1}{5}+\\dfrac{1}{7}+\\dfrac{1}{11} \\right)}{13.\\left( \\dfrac{1}{4}-\\dfrac{1}{5}+\\dfrac{1}{7}+\\dfrac{1}{11} \\right)} \\\\ = \\dfrac{3}{13} $"}]}],"id_ques":148},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":10,"ques":"Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c $ F = \\left( \\dfrac{112}{13.20} + \\dfrac{112}{20.27} + \\dfrac{112}{27.34} + ... + \\dfrac{112}{62.69} \\right) : \\left( - \\dfrac{5}{9.13} - \\dfrac{7}{9.25} - \\dfrac{13}{19.25} - \\dfrac{31}{19.69} \\right)$ l\u00e0:","select":["A. $\\dfrac{1}{12}$","B. $\\dfrac{-1}{8}$","C. $-8$","D. $-1$"],"hint":"\u0110\u1eb7t F = P : Q. Sau \u0111\u00f3 \u0111\u1eb7t th\u1eeba s\u1ed1 chung r\u1ed3i r\u00fat g\u1ecdn bi\u1ec3u th\u1ee9c. ","explain":" <span class='basic_left'> \u0110\u1eb7t F = P : Q <br\/> C\u00f3 $P = \\left( \\dfrac{112}{13.20} + \\dfrac{112}{20.27} + \\dfrac{112}{27.34} + ... + \\dfrac{112}{62.69} \\right) \\\\ = 16.\\left( \\dfrac{7}{13.20} + \\dfrac{7}{20.27} + \\dfrac{7}{27.34} + ... + \\dfrac{7}{62.69} \\right) \\\\ = 16.\\left( \\dfrac{1}{13} - \\dfrac{1}{20} + \\dfrac{1}{20} - \\dfrac{1}{27} + \\dfrac{1}{27} - \\dfrac{1}{34} + ... + \\dfrac{1}{62} - \\dfrac{1}{69} \\right) \\\\ = 16. \\left(\\dfrac{1}{13} - \\dfrac{1}{69} \\right) $ <br\/> C\u00f3 $ Q = -\\left( \\dfrac{5}{9.13} + \\dfrac{7}{9.25} + \\dfrac{13}{19.25} + \\dfrac{31}{19.69} \\right) \\\\ = -\\dfrac{1}{9} . \\left( \\dfrac{5}{13} + \\dfrac{7}{25} \\right) - \\dfrac{1}{19} . \\left( \\dfrac{13}{25} + \\dfrac{31}{69} \\right) \\\\ = -\\dfrac{1}{9} . \\dfrac{125+91}{13.25} - \\dfrac{1}{19} . \\dfrac{897+775}{25.69} \\\\ = -\\dfrac{24}{13.25} - \\dfrac{88}{25.69} \\\\ = -2 . \\left( \\dfrac{1}{13} - \\dfrac{1}{25} + \\dfrac{1}{25} - \\dfrac{1}{69} \\right) \\\\ = -2 . \\left( \\dfrac{1}{13} - \\dfrac{1}{69} \\right)$ <br\/>Suy ra $ F = P : Q = 16 : (-2) = -8$ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> <br\/>","column":2}]}],"id_ques":149},{"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":[[["1"],["5"]]],"list":[{"point":10,"width":50,"content":"","type_input":"","ques":" \u0110i\u1ec1n k\u1ebft qu\u1ea3 c\u1ee7a v\u00e0o \u00f4 tr\u1ed1ng <br\/> $ G = \\left( -0,75 - \\dfrac{1}{4} \\right) : (-5) + \\dfrac{1}{15} - \\left(\\dfrac{-1}{5} \\right) : (-3) $= <div class=\"frac123\"><div class=\"ts\">_input_<\/div><div class=\"ms\">_input_<\/div><\/div>","hint":" \u00c1p d\u1ee5ng qui t\u1eafc chia hai s\u1ed1 h\u1eefu t\u1ec9.","explain":" Ta c\u00f3: $ G = \\left( -0,75 - \\dfrac{1}{4} \\right) : (-5) + \\dfrac{1}{15} - \\left(\\dfrac{-1}{5} \\right) : (-3) \\\\ = \\left( \\dfrac{-3}{4} - \\dfrac{1}{4} \\right) : (-5) + \\dfrac{1}{15} - \\left( \\dfrac{-1}{5} . \\dfrac{1}{-3} \\right) \\\\ = \\left( (-1):(-5) \\right) + \\dfrac{1}{15} - \\dfrac{1}{15} \\\\ = \\dfrac{1}{5} $ <br\/> <br\/> <span class='basic_pink'> Gi\u00e1 tr\u1ecb c\u1ee7a G l\u00e0 $\\dfrac{1}{5}$.<\/span><\/span> <br\/>"}]}],"id_ques":150}],"lesson":{"save":0,"level":3}}

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)

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