{"segment":[{"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":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai4/lv2/img\/11.jpg' \/><\/center> Gi\u00e1 tr\u1ecb l\u1edbn nh\u1ea5t c\u1ee7a bi\u1ec3u th\u1ee9c $E = 8 - 6|x - 7| $ b\u1eb1ng: ","select":["A. $ 6 $ ","B. $ 7 $ ","C. $ 8 $ ","D. $ 1 $ "],"hint":" $E \\leq a$ th\u00ec $a$ l\u00e0 GTLN c\u1ee7a $E.$ ","explain":" Ta c\u00f3: $|x - 7| \\geq 0 \\quad \\forall x \\in \\mathbb{Q} \\\\ \\Rightarrow -6|x - 7| \\leq 0 \\\\ \\Rightarrow E = 8 - 6|x - 7| \\leq 8 $ <br\/> Do \u0111\u00f3 GTLN c\u1ee7a $E = 8$ khi $x - 7 = 0,$ t\u1ee9c l\u00e0 $x = 7$. <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 C. <\/span><\/span> <br\/>","column":2}]}],"id_ques":171},{"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/lop7/toan/daiso/bai4/lv2/img\/11.jpg' \/><\/center> Gi\u00e1 tr\u1ecb nh\u1ecf nh\u1ea5t c\u1ee7a bi\u1ec3u th\u1ee9c $M = |x - 7| + 1 - x$ b\u1eb1ng: ","select":["A. $ -5 $ ","B. $ -6 $ ","C. $ 6 $ ","D. $ 0 $ "],"hint":" $M \\geq a$ th\u00ec $a$ l\u00e0 GTNN c\u1ee7a $M.$ ","explain":" $M = |x - 7| + 1 - x$ <br\/> * N\u1ebfu $x - 7 \\geq 0 \\Leftrightarrow x \\geq 7 $ th\u00ec $M = x - 7 + 1 - x = -6 $ <br\/> * N\u1ebfu $ x < 7 $ th\u00ec $M = 7 - x + 1 - x = 8 - 2x $ <br\/> $\\quad$ V\u00ec $x < 7$ n\u00ean $ -2x > -14 \\Rightarrow M > 8 - 14 = -6$ <br\/> Nh\u01b0 v\u1eady $M \\geq -6$. Suy ra GTNN c\u1ee7a M b\u1eb1ng $-6$ khi $ x - 7 = 0$ hay $x = 7$ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 B. <\/span><\/span> <br\/>","column":2}]}],"id_ques":172},{"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":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai4/lv2/img\/11.jpg' \/><\/center> T\u00ecm $x$, bi\u1ebft: $ |3x - 5| - \\dfrac{1}{7} = \\dfrac{1}{3} $ ","select":["A. $ x = \\dfrac{-115}{63} $ ","B. $ x = \\dfrac{95}{63}$ ","C. $ x \\in \\left\\{ \\dfrac{115}{63}; \\dfrac{95}{63} \\right\\} $ ","D. $ x \\in \\left\\{ \\dfrac{-115}{63}; \\dfrac{95}{63} \\right\\} $ "],"explain":" Ta c\u00f3: $|3x - 5| - \\dfrac{1}{7} = \\dfrac{1}{3} \\\\ \\Leftrightarrow |3x - 5| = \\dfrac{1}{3} + \\dfrac{1}{7} = \\dfrac{10}{21} $ <br\/> Suy ra: $ 3x - 5 = \\dfrac{10}{21}$ ho\u1eb7c $3x - 5 = \\dfrac{-10}{21}$ <br\/> X\u00e9t $3x - 5 = \\dfrac{10}{21} \\Rightarrow 3x = \\dfrac{10}{21} + 5 = \\dfrac{115}{21} \\Rightarrow x = \\dfrac{115}{21} : 3 = \\dfrac{115}{63}$ <br\/> X\u00e9t $3x - 5 = \\dfrac{-10}{21} \\Rightarrow 3x = \\dfrac{-10}{21} + 5 = \\dfrac{95}{21} \\Rightarrow x = \\dfrac{95}{21} : 3 = \\dfrac{95}{63}$ <br\/> V\u1eady $ x \\in \\left\\{ \\dfrac{115}{63}; \\dfrac{95}{63} \\right\\} $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> <br\/>","column":2}]}],"id_ques":173},{"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/lop7/toan/daiso/bai4/lv2/img\/11.jpg' \/><\/center> T\u00ecm $x$, bi\u1ebft: $0,45 - |1,3 - x| = 0$ ","select":["A. $ x \\in \\lbrace 0,85; 1,75 \\rbrace$ ","B. $ x \\in \\lbrace -0,85; 1,75 \\rbrace$ ","C. $ x \\in \\lbrace 0,85; -1,75 \\rbrace$ ","D. $ x \\in \\lbrace -0,85; -1,75 \\rbrace$ "],"explain":" Ta c\u00f3: $0,45 - |1,3 - x| = 0 \\Leftrightarrow |1,3 - x| = 0,45 $ <br\/> Suy ra: $ 1,3 - x = 0,45$ ho\u1eb7c $1,3 - x = -0,45$ <br\/> X\u00e9t $ 1,3 - x = 0,45 \\Rightarrow x = 1,3 - 0,45 = 0,85$ <br\/> X\u00e9t $1,3 - x = -0,45 \\Rightarrow x = 1,3 + 0,45 = 1,75$ <br\/> V\u1eady $ x \\in \\lbrace 0,85; 1,75 \\rbrace$ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> <br\/>","column":2}]}],"id_ques":174},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["0"]]],"list":[{"point":5,"width":50,"content":"","type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai4/lv2/img\/10.jpg' \/><\/center> T\u00ednh gi\u00e1 tr\u1ecb nh\u1ecf nh\u1ea5t c\u1ee7a bi\u1ec3u th\u1ee9c P = |x + 1,5| <br\/> \u0110\u00e1p \u00e1n: min P = _input_","hint":" $P \\geq a$ th\u00ec $a$ l\u00e0 GTNN c\u1ee7a $P.$ ","explain":" $P = |x + 1,5|$ <br\/> Ta c\u00f3: $|x + 1,5| \\geq 0 \\quad \\forall x \\in \\mathbb{Q}$ <br\/> Suy ra GTNN c\u1ee7a P l\u00e0 0 khi $ x + 1,5 = 0$ hay $x = -1,5$ <br\/> <br\/> <span class='basic_pink'> V\u1eady min $P = 0 \\Leftrightarrow x = -1,5 $ <\/span><\/span> <br\/>"}]}],"id_ques":175},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["-9"],["10"]]],"list":[{"point":5,"width":50,"content":"","type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai4/lv2/img\/10.jpg' \/><\/center> T\u00ednh gi\u00e1 tr\u1ecb nh\u1ecf nh\u1ea5t c\u1ee7a bi\u1ec3u th\u1ee9c $P = |x - 2| - \\dfrac{9}{10}$ <br\/> \u0110\u00e1p \u00e1n: min P <div class=\"frac123\"><div class=\"ts\">_input_<\/div><div class=\"ms\">_input_<\/div><\/div>","hint":" $P \\geq a$ th\u00ec $a$ l\u00e0 GTNN c\u1ee7a $P.$ ","explain":" $P = |x - 2| - \\dfrac{9}{10}$ <br\/> Ta c\u00f3: $|x - 2| \\geq 0 \\quad \\forall x \\in \\mathbb{Q} \\Rightarrow |x - 2| - \\dfrac{9}{10} \\geq \\dfrac{-9}{10}$ <br\/> Suy ra GTNN c\u1ee7a P l\u00e0 $\\dfrac{-9}{10}$ khi $ |x - 2| = 0 \\Rightarrow x = 2$ <br\/> <br\/> <span class='basic_pink'> V\u1eady min P = $\\dfrac{-9}{10} \\Leftrightarrow x = 2$<\/span><\/span> <br\/>"}]}],"id_ques":176},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["0"]]],"list":[{"point":5,"width":50,"content":"","type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai4/lv2/img\/10.jpg' \/><\/center> Gi\u00e1 tr\u1ecb l\u1edbn nh\u1ea5t c\u1ee7a bi\u1ec3u th\u1ee9c $P = -|2x - 1| $ b\u1eb1ng: <br\/> max P = _input_","hint":" $P \\leq a$ th\u00ec $a$ l\u00e0 GTLN c\u1ee7a $P.$ ","explain":" $P = -|2x - 1| $ <br\/> Ta c\u00f3: $|2x - 1| \\geq 0 \\quad \\forall x \\in \\mathbb{Q} \\Rightarrow -|2x - 1| \\leq 0$ <br\/> Suy ra GTLN c\u1ee7a P l\u00e0 $0$ <br\/> khi $ |2x - 1| = 0 \\Rightarrow x = \\dfrac{1}{2}$ <br\/> <br\/> <span class='basic_pink'> V\u1eady max P = $0 \\Leftrightarrow x = \\dfrac{1}{2}$<\/span><\/span> <br\/>"}]}],"id_ques":177},{"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/lop7/toan/daiso/bai4/lv2/img\/10.jpg' \/><\/center> Khi $x = \\dfrac{-1}{2}$ th\u00ec bi\u1ec3u th\u1ee9c $G = |x + 1| + |x + 2| + |x|$ c\u00f3 gi\u00e1 tr\u1ecb l\u00e0: ","select":["A. $ 3\\dfrac{1}{2} $","B. $ 1\\dfrac{3}{4} $","C. $ 2 $","D. $ 2\\dfrac{1}{2} $"],"hint":" Thay $x = \\dfrac{-1}{2}$ v\u00e0o bi\u1ec3u th\u1ee9c G r\u1ed3i th\u1ef1c hi\u1ec7n ph\u00e9p t\u00ednh. ","explain":" Khi $ x = \\dfrac{-1}{2}$ th\u00ec $ G = \\left | \\dfrac{-1}{2} + 1 \\right | + \\left | \\dfrac{-1}{2} + 2\\right | + \\left | \\dfrac{-1}{2}\\right | \\\\ = \\left | \\dfrac{1}{2}\\right | + \\left | \\dfrac{3}{2}\\right | + \\left | \\dfrac{-1}{2}\\right | \\\\ = \\dfrac{1}{2} + \\dfrac{3}{2} + \\dfrac{1}{2} = \\dfrac{5}{2} = 2\\dfrac{1}{2}$ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> <br\/>","column":2}]}],"id_ques":178},{"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/lop7/toan/daiso/bai4/lv2/img\/10.jpg' \/><\/center> Khi $x = 0,2$ th\u00ec bi\u1ec3u th\u1ee9c $H = |3x - 1| + |3x - 5| $ c\u00f3 gi\u00e1 tr\u1ecb l\u00e0: ","select":["A. $ 4,8 $","B. $ 0,5 $","C. $ -4,8 $","D. $ 3,6 $"],"hint":" Thay $x = 0,2$ v\u00e0o H r\u1ed3i th\u1ef1c hi\u1ec7n ph\u00e9p t\u00ednh.","explain":" Khi $ x = 0,2 $ th\u00ec $ H = |3 . 0,2 - 1| + |3. 0,2 - 5| \\\\ = |0,6 - 1| + |0,6 - 5| \\\\ = |-0,4| + |-4,4| = 0,4 + 4,4 = 4,8 $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> <br\/>","column":2}]}],"id_ques":179},{"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/lop7/toan/daiso/bai4/lv2/img\/9.jpg' \/><\/center> T\u00ecm $x \\in \\mathbb{Q}$, bi\u1ebft: <br\/> $\\mid x + \\dfrac{3}{4} \\mid - \\dfrac{1}{3} = 0 $ ","select":["A. $ x = \\dfrac{-5}{12} $ ho\u1eb7c $ x = \\dfrac{13}{12} $","B. $ x = \\dfrac{-5}{12} $ ho\u1eb7c $ x = \\dfrac{-13}{12} $","C. $ x = \\dfrac{-1}{12} $ ho\u1eb7c $ x = \\dfrac{-5}{12} $","D. $ x = \\dfrac{1}{12} $ ho\u1eb7c $ x = \\dfrac{-5}{12} $"],"hint":" N\u1ebfu $\\mid x \\mid = a $ ( v\u1edbi $ a \\geq 0 $) th\u00ec $ x = \\pm a. $ ","explain":"<span class='basic_left'> Ta c\u00f3: $\\mid x + \\dfrac{3}{4} \\mid - \\dfrac{1}{3} = 0$ <br\/> $ \\Leftrightarrow \\mid x + \\dfrac{3}{4} \\mid = \\dfrac{1}{3}$ <br\/> V\u00ec $\\mid x + \\dfrac{3}{4} \\mid = \\dfrac{1}{3}$ n\u00ean $x + \\dfrac{3}{4} = \\pm \\dfrac{1}{3}$ <br\/> X\u00e9t $ x + \\dfrac{3}{4} = \\dfrac{1}{3} \\Rightarrow x = \\dfrac{1}{3} - \\dfrac{3}{4} = \\dfrac{-5}{12} $ <br\/> X\u00e9t $ x + \\dfrac{3}{4} = \\dfrac{-1}{3} \\Rightarrow x = \\dfrac{-1}{3} - \\dfrac{3}{4} = \\dfrac{-13}{12}$ <br\/> V\u1eady $ x \\in \\left\\{ \\dfrac{-5}{12}; \\dfrac{-13}{12} \\right\\} $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> <br\/>","column":2}]}],"id_ques":180},{"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/lop7/toan/daiso/bai4/lv2/img\/9.jpg' \/><\/center> T\u00ecm $x \\in \\mathbb{Q}$, bi\u1ebft: <br\/> $ 3,6 - \\mid x - 0,4 \\mid = 0 $ ","select":["A. $ x = 4 $ ho\u1eb7c $ x = -4 $","B. $ x = 4 $ ho\u1eb7c $ x = -3,2 $","C. $ x = -4 $ ho\u1eb7c $ x = -3,2 $","D. $ x = 4 $ "],"hint":" N\u1ebfu $\\mid x \\mid = a $ ( v\u1edbi $ a \\geq 0 $) th\u00ec $ x = \\pm a. $ ","explain":" <span class='basic_left'> Ta c\u00f3: $ 3,6 - \\mid x - 0,4 \\mid = 0$ <br\/> $ \\Leftrightarrow \\mid x - 0,4 \\mid = 3,6 $ <br\/> V\u00ec $ \\mid x - 0,4 \\mid = 3,6 $ n\u00ean $ x - 0,4 = \\pm 3,6 $ <br\/> X\u00e9t $ x - 0,4 = 3,6 \\Rightarrow x = 3,6 + 0,4 = 4 $ <br\/> X\u00e9t $x - 0,4 = -3,6 \\Rightarrow x = -3,6 + 0,4 = -3,2 $ <br\/> V\u1eady $ x \\in \\lbrace 4; -3,2 \\rbrace $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 B.<\/span><\/span> <br\/>","column":2}]}],"id_ques":181},{"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/lop7/toan/daiso/bai4/lv2/img\/9.jpg' \/><\/center> T\u00ecm $x$ bi\u1ebft: $\\mid x + 3,19 \\mid = 2,05 $ ","select":["A. $ x = -1,14 $ ho\u1eb7c $ x = -5,24$","B. $ x = -1,14 $ ","C. $ x = 5,24$","D. $ x = 1,14 $ ho\u1eb7c $ x = 5,24$"],"hint":" N\u1ebfu $\\mid x \\mid = a $ ( v\u1edbi $ a \\geq 0 $) th\u00ec $ x = \\pm a. $ ","explain":" V\u00ec $\\mid x + 3,19 \\mid = 2,05 $ n\u00ean $ x + 3,19 = \\pm 2,05 $ <br\/> X\u00e9t $ x + 3,19 = 2,05 \\Rightarrow x = 2,05 - 3,19 = -1,14 $ <br\/> X\u00e9t $ x + 3,19 = -2,05 \\Rightarrow x = -2,05 - 3,19 = -5,24 $ <br\/> V\u1eady $ x \\in \\lbrace -1,14; -5,24 \\rbrace $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span><\/span> <br\/>","column":2}]}],"id_ques":182},{"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":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai4/lv2/img\/9.jpg' \/><\/center> T\u00ecm $x$, bi\u1ebft: $ \\left | \\dfrac{2}{3}x + \\dfrac{1}{2} \\right | = \\dfrac{5}{3} $ ","select":["A. $ x = \\dfrac{11}{12} $","B. $ x = \\dfrac{-29}{12} $","C. $ x = \\dfrac{-13}{4} $ ho\u1eb7c $ x = \\dfrac{7}{4} $","D. $ x = \\dfrac{7}{4} $ ho\u1eb7c $ x = \\dfrac{13}{4} $"],"hint":" N\u1ebfu $\\mid x \\mid = a $ ( v\u1edbi $ a \\geq 0 $) th\u00ec $ x = \\pm a. $ ","explain":" <span class='basic_left'> V\u00ec $ \\left | \\dfrac{2}{3}x + \\dfrac{1}{2} \\right | = \\dfrac{5}{3} $ n\u00ean $ \\dfrac{2}{3}x + \\dfrac{1}{2} = \\pm \\dfrac{5}{3} $ <br\/> <br\/> X\u00e9t $ \\dfrac{2}{3}x + \\dfrac{1}{2} = \\dfrac{-5}{3} \\Rightarrow \\dfrac{2}{3}x = \\dfrac{-5}{3} - \\dfrac{1}{2} = \\dfrac{-13}{6} \\Rightarrow x = \\dfrac{-13}{6} : \\dfrac{2}{3} = \\dfrac{-13}{4} $ <br\/> <br\/> X\u00e9t $ \\dfrac{2}{3}x + \\dfrac{1}{2} = \\dfrac{5}{3} \\Rightarrow \\dfrac{2}{3}x = \\dfrac{5}{3} - \\dfrac{1}{2} = \\dfrac{7}{6} \\Rightarrow x = \\dfrac{7}{6} : \\dfrac{2}{3} = \\dfrac{7}{4} $ <br\/> V\u1eady $ x \\in \\left\\{ \\dfrac{-13}{4}; \\dfrac{7}{4} \\right\\} $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 C.<\/span><\/span> <br\/>","column":2}]}],"id_ques":183},{"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/lop7/toan/daiso/bai4/lv2/img\/9.jpg' \/><\/center> T\u00ecm $x$, bi\u1ebft: $ 8 - \\left | x - \\dfrac{1}{3} \\right | = 9 $ ","select":["A. $ x = \\dfrac{-2}{3} $","B. $ x = \\dfrac{4}{3} $","C. $ x = \\dfrac{-2}{3} $ ho\u1eb7c $ x = \\dfrac{4}{3} $","D. $ x = \\varnothing $"],"hint":" N\u1ebfu $\\mid x \\mid = a $ ( v\u1edbi $ a \\geq 0 $) th\u00ec $ x = \\pm a. $ ","explain":" Ta c\u00f3: $ 8 - \\left | x - \\dfrac{1}{3} \\right | = 9 $ <br\/> $ \\Leftrightarrow \\left | x - \\dfrac{1}{3} \\right | = 8 - 9 = -1 < 0 $ ( v\u00f4 l\u00fd v\u00ec $ \\mid a \\mid \\geq 0 \\quad \\forall a \\in \\mathbb{Q} $ ) <br\/> V\u1eady kh\u00f4ng t\u1ed3n t\u1ea1i gi\u00e1 tr\u1ecb c\u1ee7a $x$ th\u1ecfa m\u00e3n b\u00e0i to\u00e1n. <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 D.<\/span><\/span> <br\/>","column":2}]}],"id_ques":184},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["10"]]],"list":[{"point":5,"width":50,"content":"","type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai4/lv2/img\/9.jpg' \/><\/center>Vi\u1ebft k\u1ebft qu\u1ea3 c\u1ee7a bi\u1ec3u th\u1ee9c A v\u00e0o \u00f4 tr\u1ed1ng <br\/> $ A = \\mid -(315 . 4 + 275) + 4 . 315 - (10 - 275) \\mid $= _input_","hint":" B\u1ecf ngo\u1eb7c r\u1ed3i r\u00fat g\u1ecdn ph\u00e9p t\u00ednh ","explain":" Ta c\u00f3: $ -(315 . 4 + 275) + 4 . 315 - (10 - 275) \\\\ = -315 . 4 - 275 + 4 . 315 - 10 + 275 \\\\ = (-315 . 4 + 4 . 315) + (-275 + 275) - 10 \\\\ = 0 + 0 - 10 = -10 $ <br\/> Suy ra $A = \\mid -10 \\mid = 10 $ <br\/> <span class='basic_pink'> Gi\u00e1 tr\u1ecb c\u1ee7a A l\u00e0 $ 10 $.<\/span><\/span> <br\/>"}]}],"id_ques":185},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["1"]]],"list":[{"point":5,"width":50,"content":"","type_input":"","ques":" Gi\u00e1 tr\u1ecb bi\u1ec3u th\u1ee9c: $ B = \\mid 2,7 - (-4,3) + (-8,5) - (-0,5) \\mid $= _input_","explain":" Ta c\u00f3: $ 2,7 - (-4,3) + (-8,5) - (-0,5) \\\\ = 2,7 + 4,3 - 8,5 + 0,5 \\\\ = (2,7 + 4,3) - ( 8,5 - 0,5) \\\\ = 7 - 8 \\\\ = -1 $ <br\/> Suy ra $B = \\mid -1 \\mid = 1 $ <br\/> <span class='basic_pink'> Gi\u00e1 tr\u1ecb c\u1ee7a B l\u00e0 $ 1 $.<\/span><\/span> <br\/>"}]}],"id_ques":186},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["4,7"]]],"list":[{"point":5,"width":50,"content":"","type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai4/lv2/img\/11.jpg' \/><\/center> Gi\u00e1 tr\u1ecb bi\u1ec3u th\u1ee9c: $ C = \\mid6,3 + (-3,7) + 2,4 + (-0,3) \\mid $= _input_ ","hint":" Nh\u00f3m s\u1ed1 h\u1ea1ng th\u00edch h\u1ee3p r\u1ed3i th\u1ef1c hi\u1ec7n ph\u00e9p t\u00ednh ","explain":" Ta c\u00f3: $ 6,3 + (-3,7) + 2,4 + (-0,3) \\\\ = (6,3 + 2,4) + [(-3,7) + (-0,3)] \\\\ = 8,7 + [-(3,7 + 0,3)] \\\\ = 8,7 + (-4) = 4,7 $ <br\/> Suy ra $C = \\mid 4,7 \\mid = 4,7 $ <br\/> <span class='basic_pink'> Gi\u00e1 tr\u1ecb c\u1ee7a C l\u00e0 $ 4,7 $.<\/span><\/span> <br\/>"}]}],"id_ques":187},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["0"]]],"list":[{"point":5,"width":50,"content":"","type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai4/lv2/img\/11.jpg' \/><\/center> Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c $ D = \\mid (-4,9) + 5,5 + 4,9 + (-5,5) \\mid$ =_input_","hint":" Nh\u00f3m s\u1ed1 h\u1ea1ng th\u00edch h\u1ee3p r\u1ed3i th\u1ef1c hi\u1ec7n ph\u00e9p t\u00ednh ","explain":" Ta c\u00f3: $ (-4,9) + 5,5 + 4,9 + (-5,5) \\\\ = [(-4,9) + 4,9] + [5,5 + (-5,5)] \\\\ = 0 + 0 = 0 $ <br\/>Suy ra $D = \\mid 0 \\mid = 0 $ <br\/> <span class='basic_pink'> Gi\u00e1 tr\u1ecb c\u1ee7a D l\u00e0 $ 0 $.<\/span><\/span> <br\/>"}]}],"id_ques":188},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["2,4"]]],"list":[{"point":5,"width":50,"content":"","type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai4/lv2/img\/11.jpg' \/><\/center> Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c $ E = \\mid 3,1 + 2,4 + (-5,6) + (-3,1) + 5,6 \\mid$ = _input_","hint":" Nh\u00f3m s\u1ed1 h\u1ea1ng th\u00edch h\u1ee3p r\u1ed3i th\u1ef1c hi\u1ec7n ph\u00e9p t\u00ednh ","explain":" Ta c\u00f3: $3,1 + 2,4 + (-5,6) + (-3,1) + 5,6 \\\\ = [3,1 + (-3,1)] + [(-5,6) + 5,6] + 2,4 \\\\ = 0 + 0 + 2,4 = 2,4 $ <br\/> Suy ra $E = \\mid 2,4 \\mid = 2,4 $<br\/> <span class='basic_pink'> Gi\u00e1 tr\u1ecb c\u1ee7a E l\u00e0 $ 2,4 $.<\/span><\/span> <br\/>"}]}],"id_ques":189},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["39"]]],"list":[{"point":5,"width":50,"content":"","type_input":"","ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai4/lv2/img\/11.jpg' \/><\/center> Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c $ F = \\mid (-4,7) . (3,9) + 3,9 . (-5,3) \\mid $= _input_","hint":" Nh\u00f3m s\u1ed1 h\u1ea1ng th\u00edch h\u1ee3p r\u1ed3i th\u1ef1c hi\u1ec7n ph\u00e9p t\u00ednh ","explain":" Ta c\u00f3: $ (-4,7) . (3,9) + 3,9 . (-5,3) \\\\ = 3,9 . [(-4,7) + (-5,3)] \\\\ = 3,9 . [-(4,7 + 5,3)] \\\\ = 3,9 . (-10) = -39 $ <br\/> Suy ra $F = \\mid -39 \\mid = 39 $ <br\/> <span class='basic_pink'> Gi\u00e1 tr\u1ecb c\u1ee7a F l\u00e0 $ 39 $.<\/span><\/span> <br\/>"}]}],"id_ques":190}],"lesson":{"save":0,"level":2}}