{"segment":[{"time":24,"part":[{"title":"V\u1ebd \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1.","title_trans":"","temp":"coordinates","correct":[["2,-1","1,-0.5","3,-1.5","4,-2","-2,1","-1,0.5","-3,1.5","-4,2"]],"list":[{"point":5,"toa_do":[["0","0",""]],"is_click":1,"name_toado_click":"A","draw_line":1,"ques":"V\u1ebd \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = \\dfrac{-1}{2}x$ <br\/> <br\/>_inputduongthang_ <br\/> H\u00e3y click th\u00eam m\u1ed9t \u0111i\u1ec3m thu\u1ed9c \u0111\u1ed3 th\u1ecb \u0111\u1ec3 v\u1ebd \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1.","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> B\u01b0\u1edbc 1: X\u00e1c \u0111\u1ecbnh m\u1ed9t \u0111i\u1ec3m A thu\u1ed9c \u0111\u1ed3 th\u1ecb (kh\u00e1c g\u1ed1c O) b\u1eb1ng c\u00e1ch cho x m\u1ed9t gi\u00e1 tr\u1ecb kh\u00e1c 0 r\u1ed3i t\u00ecm gi\u00e1 tr\u1ecb t\u01b0\u01a1ng \u1ee9ng c\u1ee7a y. <br\/> B\u01b0\u1edbc 2: V\u1ebd \u0111i\u1ec3m A(x; y) <br\/> B\u01b0\u1edbc 3: V\u1ebd \u0111\u01b0\u1eddng th\u1eb3ng OA ta \u0111\u01b0\u1ee3c \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 \u0111\u00e3 cho. <\/span> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> <br\/> Cho $y = \\dfrac{-1}{2}x ,$ v\u1edbi $x = 2$ th\u00ec $y = -1$ <br\/> V\u1ebd \u0111i\u1ec3m $A(2; -1).$ \u0110\u01b0\u1eddng th\u1eb3ng OA l\u00e0 \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = \\dfrac{-1}{2}x$ <br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai17/lv2/img\/D7B17-13.png' \/><\/center> "}]}],"id_ques":781},{"time":24,"part":[{"title":"V\u1ebd \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1.","title_trans":"","temp":"coordinates","correct":[["2,3","1,1.5","3,4.5","-2,-3","-1,-1.5","-3,-4.5"]],"list":[{"point":5,"toa_do":[["0","0",""]],"is_click":1,"name_toado_click":"A","draw_line":1,"ques":"V\u1ebd \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = \\dfrac{3}{2}x$ <br\/> <br\/>_inputduongthang_ <br\/> H\u00e3y click th\u00eam m\u1ed9t \u0111i\u1ec3m thu\u1ed9c \u0111\u1ed3 th\u1ecb \u0111\u1ec3 v\u1ebd \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1.","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> B\u01b0\u1edbc 1: X\u00e1c \u0111\u1ecbnh m\u1ed9t \u0111i\u1ec3m A thu\u1ed9c \u0111\u1ed3 th\u1ecb (kh\u00e1c g\u1ed1c O) b\u1eb1ng c\u00e1ch cho x m\u1ed9t gi\u00e1 tr\u1ecb kh\u00e1c 0 r\u1ed3i t\u00ecm gi\u00e1 tr\u1ecb t\u01b0\u01a1ng \u1ee9ng c\u1ee7a y. <br\/> B\u01b0\u1edbc 2: V\u1ebd \u0111i\u1ec3m A(x; y) <br\/> B\u01b0\u1edbc 3: V\u1ebd \u0111\u01b0\u1eddng th\u1eb3ng OA ta \u0111\u01b0\u1ee3c \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 \u0111\u00e3 cho. <\/span> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> Cho $y = \\dfrac{3}{2}x ,$ v\u1edbi x = 2 th\u00ec y = 3 <br\/> V\u1ebd \u0111i\u1ec3m A(2; 3). \u0110\u01b0\u1eddng th\u1eb3ng OA l\u00e0 \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = \\dfrac{3}{2}x$ <br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai17/lv2/img\/D7B17-12.png' \/><\/center> "}]}],"id_ques":782},{"time":24,"part":[{"title":"V\u1ebd \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1.","title_trans":"","temp":"coordinates","correct":[["3,-4","-3,4"]],"list":[{"point":5,"toa_do":[["0","0",""]],"is_click":1,"name_toado_click":"A","draw_line":1,"ques":"V\u1ebd \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = -1\\dfrac{1}{3}x$ <br\/> <br\/>_inputduongthang_ <br\/> H\u00e3y click th\u00eam m\u1ed9t \u0111i\u1ec3m thu\u1ed9c \u0111\u1ed3 th\u1ecb \u0111\u1ec3 v\u1ebd \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1.","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> B\u01b0\u1edbc 1: X\u00e1c \u0111\u1ecbnh m\u1ed9t \u0111i\u1ec3m A thu\u1ed9c \u0111\u1ed3 th\u1ecb (kh\u00e1c g\u1ed1c O) b\u1eb1ng c\u00e1ch cho x m\u1ed9t gi\u00e1 tr\u1ecb kh\u00e1c 0 r\u1ed3i t\u00ecm gi\u00e1 tr\u1ecb t\u01b0\u01a1ng \u1ee9ng c\u1ee7a y. <br\/> B\u01b0\u1edbc 2: V\u1ebd \u0111i\u1ec3m A(x; y) <br\/> B\u01b0\u1edbc 3: V\u1ebd \u0111\u01b0\u1eddng th\u1eb3ng OA ta \u0111\u01b0\u1ee3c \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 \u0111\u00e3 cho. <\/span> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> <br\/> Cho $y = -1\\dfrac{1}{3}x = \\dfrac{-4}{3}x ,$ v\u1edbi $x = 3$ th\u00ec $y = -4$ <br\/> V\u1ebd \u0111i\u1ec3m $A(3; -4).$ \u0110\u01b0\u1eddng th\u1eb3ng OA l\u00e0 \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = -1\\dfrac{1}{3}x$ <br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai17/lv2/img\/D7B17-11.png' \/><\/center> "}]}],"id_ques":783},{"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":" \u0110\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = \\dfrac{1}{3}x $ l\u00e0: ","select":["A. \u0110\u01b0\u1eddng th\u1eb3ng $OA$ v\u1edbi $O(0; 0)$ v\u00e0 $A(1; 3)$ ","B. \u0110\u01b0\u1eddng th\u1eb3ng $OA$ v\u1edbi $O(0; 0)$ v\u00e0 $A(-1; -3)$","C. \u0110\u01b0\u1eddng th\u1eb3ng $OA$ v\u1edbi $O(0; 0)$ v\u00e0 $A(3; 1)$","D. \u0110\u01b0\u1eddng th\u1eb3ng $OA$ v\u1edbi $O(0; 0)$ v\u00e0 $A(-3; 1)$"],"explain":" \u0110\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = \\dfrac{1}{3}x $ \u0111i qua g\u1ed1c t\u1ecda \u0111\u1ed9 $O(0;0)$ <br\/> * Cho $x = 1$ th\u00ec $y = \\dfrac{1}{3} \\neq 3 $ <br\/> <br\/> * Cho $x = -1$ th\u00ec $y = \\dfrac{-1}{3} \\neq -3 $ <br\/> * Cho x = 3 th\u00ec y = 1 <br\/> Suy ra $A(3; 1)$ thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 <br\/> V\u1eady \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = \\dfrac{1}{3}x $ l\u00e0 \u0111\u01b0\u1eddng th\u1eb3ng $OA$ v\u1edbi $O(0; 0)$ v\u00e0 $A(3; 1)$ <br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai17/lv2/img\/D7B17-17.png' \/><\/center><br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 C. <\/span> <\/span>","column":1}]}],"id_ques":784},{"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":" \u0110\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = -2x$ v\u1edbi $x \\geq 0$ n\u1eb1m \u1edf g\u00f3c ph\u1ea7n t\u01b0 th\u1ee9: ","select":["A. (I) ","B. (II) ","C. (III) ","D. (IV) "],"explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> \u0110\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = ax $: <br\/> N\u1ebfu a > 0 th\u00ec \u0111\u1ed3 th\u1ecb n\u1eb1m trong g\u00f3c ph\u1ea7n t\u01b0 th\u1ee9 (I) v\u00e0 (III) <br\/> N\u1ebfu a < 0 th\u00ec \u0111\u1ed3 th\u1ecb n\u1eb1m trong g\u00f3c ph\u1ea7n t\u01b0 th\u1ee9 (II) v\u00e0 (IV) <\/span> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> \u0110\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = -2x $ c\u00f3 $-2 < 0$ <br\/> Suy ra n\u00f3 n\u1eb1m trong g\u00f3c ph\u1ea7n t\u01b0 th\u1ee9 (II), (IV) <br\/> Nh\u01b0ng v\u00ec $x \\geq 0 $ n\u00ean \u0111\u1ed3 th\u1ecb n\u1eb1m trong g\u00f3c ph\u1ea7n t\u01b0 th\u1ee9 (IV). <\/span> <br\/><br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 D. <\/span><br\/>","column":4}]}],"id_ques":785},{"time":24,"part":[{"title":"Ch\u1ecdn <u>nh\u1eefng<\/u> \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"Ch\u1ecdn \u0111\u01b0\u1ee3c nhi\u1ec1u \u0111\u00e1p \u00e1n","temp":"checkbox","correct":[["1","2","4"]],"list":[{"point":5,"img":"","ques":"Cho h\u00e0m s\u1ed1 y = 4x. Ba \u0111i\u1ec3m n\u00e0o trong b\u1ed1n \u0111i\u1ec3m d\u01b0\u1edbi \u0111\u00e2y th\u1eb3ng h\u00e0ng? ","hint":"Ba \u0111i\u1ec3m th\u1eb3ng h\u00e0ng khi ch\u00fang c\u00f9ng n\u1eb1m tr\u00ean m\u1ed9t \u0111\u01b0\u1eddng th\u1eb3ng. ","column":1,"number_true":3,"select":["$A\\left(\\dfrac{-1}{2}; -2\\right)$","$B\\left(\\dfrac{1}{2}; 2\\right)$","$C(2; -6)$","$D(-2; -8)$"],"explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/>\u0110i\u1ec3m $M(x_{0};y_{0})$ thu\u1ed9c \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = f(x) $ n\u1ebfu $y_{0} = f(x_{0}) $ <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> <br\/> <span class='basic_left'> A. Thay $x = \\dfrac{-1}{2} $ v\u00e0o $y = 4x $ ta \u0111\u01b0\u1ee3c $y = 4.\\dfrac{-1}{2} = -2 $ <br\/> $\\Rightarrow $ \u0111i\u1ec3m $A\\left(\\dfrac{-1}{2}; -2\\right)$ thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = 4x .$ <br\/> B. Thay $x = \\dfrac{1}{2} $ v\u00e0o $y = 4x $ ta \u0111\u01b0\u1ee3c $y = 4.\\dfrac{1}{2} = 2 $ <br\/> $\\Rightarrow $ \u0111i\u1ec3m $B\\left(\\dfrac{1}{2}; 2\\right)$ thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = 4x. $ <br\/> C. Thay $x = 2 $ v\u00e0o $y = 4x $ ta \u0111\u01b0\u1ee3c $y = 4.2 = 8 \\neq -6 $ <br\/> $\\Rightarrow $ \u0111i\u1ec3m $C(2; -6)$ kh\u00f4ng thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = 4x .$ <br\/> D. Thay $x = -2 $ v\u00e0o $y = 4x $ ta \u0111\u01b0\u1ee3c $y = 4.(-2) = -8 $ <br\/> $\\Rightarrow $ \u0111i\u1ec3m $D(-2; -8)$ thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = 4x .$ <br\/> T\u1eeb c\u00e1c k\u1ebft qu\u1ea3 tr\u00ean ta suy ra ba \u0111i\u1ec3m A, B, D th\u1eb3ng h\u00e0ng v\u00ec c\u00f9ng thu\u1ed9c \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 y = 4x. <\/span> "}]}],"id_ques":786},{"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":" \u0110\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = \\dfrac{-1}{2} x $ l\u00e0 \u0111\u01b0\u1eddng th\u1eb3ng kh\u00f4ng \u0111i qua \u0111i\u1ec3m: ","select":["A. $M\\left(1; \\dfrac{-1}{2}\\right)$ ","B. $N\\left(\\dfrac{-1}{2}; \\dfrac{-1}{4} \\right)$ ","C. $P\\left(3; \\dfrac{-3}{2}\\right)$ ","D. $Q\\left(\\dfrac{3}{2}; \\dfrac{-3}{4} \\right)$ "],"explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/> \u0110\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = f(x) $ \u0111i qua \u0111i\u1ec3m $M(x_{0};y_{0})$ n\u1ebfu $y_{0} = f(x_{0}) $ <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> <span class='basic_left'> A. Thay $x = 1 $ v\u00e0o $y = \\dfrac{-1}{2} x $ ta \u0111\u01b0\u1ee3c $y = \\dfrac{-1}{2}.1 = \\dfrac{-1}{2} $ <br\/> $\\Rightarrow $ \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = \\dfrac{-1}{2}x $ \u0111i qua \u0111i\u1ec3m $M\\left(1; \\dfrac{-1}{2}\\right)$ <br\/> B. Thay $x = \\dfrac{-1}{2} $ v\u00e0o $y = \\dfrac{-1}{2} x $ ta \u0111\u01b0\u1ee3c $y = \\dfrac{-1}{2}.\\dfrac{-1}{2} = \\dfrac{1}{4} \\neq \\dfrac{-1}{4} $ <br\/> $\\Rightarrow $ \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = \\dfrac{-1}{2}x $ kh\u00f4ng \u0111i qua \u0111i\u1ec3m $N\\left(\\dfrac{-1}{2}; \\dfrac{-1}{4}\\right)$ <br\/> T\u01b0\u01a1ng t\u1ef1, ta th\u1ea5y \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 \u0111i qua c\u00e1c \u0111i\u1ec3m P, Q. <br\/><br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 B. <\/span><br\/>","column":2}]}],"id_ques":787},{"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":" \u0110\u01b0\u1eddng th\u1eb3ng OM trong h\u00ecnh l\u00e0 \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 y = ax. H\u00e3y x\u00e1c \u0111\u1ecbnh h\u1ec7 s\u1ed1 a <br\/><br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai17/lv2/img\/D7B17-19.png' \/><\/center> ","select":["A. $a = \\dfrac{1}{3} $","B. $a = \\dfrac{-1}{3} $ ","C. $ a = 3$ ","D. $a = -3 $ "],"explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/>B\u01b0\u1edbc 1: Thay t\u1ecda \u0111\u1ed9 c\u1ee7a \u0111i\u1ec3m M: $x = x_{0}, y = y_{0}$ v\u00e0o $y = ax $ <br\/>B\u01b0\u1edbc 2: T\u1eeb \u0111\u00f3 ta x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c $ a = \\dfrac{x_{0}}{y_{0}}$. <\/span> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> \u0110i\u1ec3m M(3; 1) thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 y = ax. <br\/> Thay $x = 3; y = 1$ v\u00e0o h\u00e0m s\u1ed1 $y = ax$ ta \u0111\u01b0\u1ee3c: <br\/> $1 = a.3 \\Rightarrow a = \\dfrac{1}{3} $ <br\/><br\/> <span class='basic_pink'>\u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 A. <\/span><br\/>","column":2}]}],"id_ques":788},{"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":" \u0110\u01b0\u1eddng th\u1eb3ng OK trong h\u00ecnh l\u00e0 \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 y = kx. H\u00e3y x\u00e1c \u0111\u1ecbnh h\u1ec7 s\u1ed1 k? <br\/> <br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai17/lv2/img\/D7B17-21.png' \/><\/center> ","select":["A. $k = \\dfrac{-1}{2} $","B. $k =\\dfrac{1}{2} $ ","C. $k = -2 $ ","D. $k = 2 $ "],"explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/>B\u01b0\u1edbc 1: Thay t\u1ecda \u0111\u1ed9 c\u1ee7a \u0111i\u1ec3m K: $x = x_{0}, y = y_{0}$ v\u00e0o $y = kx $ <br\/>B\u01b0\u1edbc 2: T\u1eeb \u0111\u00f3 ta x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c $ k = \\dfrac{x_{0}}{y_{0}}$. <\/span> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/> \u0110i\u1ec3m $K(2; -1)$ thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 y = kx. <br\/> Thay $x = 2; y = -1$ v\u00e0o h\u00e0m s\u1ed1 $y = kx$ ta \u0111\u01b0\u1ee3c: <br\/> $-1 = k.2 \\Rightarrow k = \\dfrac{-1}{2} $ <br\/><br\/> <span class='basic_pink'>\u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 A. <\/span><br\/>","column":2}]}],"id_ques":789},{"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":" \u0110\u01b0\u1eddng th\u1eb3ng OM trong h\u00ecnh l\u00e0 \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1: <br\/> <br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai17/lv2/img\/D7B17-22.png' \/><\/center> ","select":["A. $y = -2x $","B. $y = 2x $ ","C. $y = \\dfrac{1}{2}x $ ","D. $y = \\dfrac{-1}{2} x $ "],"explain":" \u0110i\u1ec3m $M(-1; 2)$ thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 y = ax. <br\/> Thay $x = -1; y = 2$ v\u00e0o h\u00e0m s\u1ed1 $y = ax$ ta \u0111\u01b0\u1ee3c: <br\/> $2 = a.(-1) \\Rightarrow a = -2 $ <br\/> \u0110\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 \u0111\u00e3 cho l\u00e0: $y = -2x $ <br\/><br\/> <span class='basic_pink'>\u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 A. <\/span><br\/>","column":2}]}],"id_ques":790},{"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":" \u0110\u01b0\u1eddng th\u1eb3ng OM trong h\u00ecnh l\u00e0 \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 n\u00e0o d\u01b0\u1edbi \u0111\u00e2y <br\/> <br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai17/lv2/img\/D7B17-23.png' \/><\/center> ","select":["A. $y = 2x $","B. $y = - x $ ","C. $y = \\dfrac{1}{2}x $ ","D. $y = \\dfrac{-1}{2} x $ "],"explain":" \u0110i\u1ec3m $M(-2; 1)$ thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = ax (a\\neq 0)$ <br\/> Thay $x = -2; y = 1$ v\u00e0o h\u00e0m s\u1ed1 $y = ax$ ta \u0111\u01b0\u1ee3c: <br\/> $1 = a.(-2) \\Rightarrow a = \\dfrac{-1}{2} $ <br\/> \u0110\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 \u0111\u00e3 cho l\u00e0: $y = \\dfrac{-1}{2}x $ <br\/><br\/> <span class='basic_pink'>\u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 D. <\/span><br\/>","column":2}]}],"id_ques":791},{"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":"T\u00ecm \u0111i\u1ec3m M tr\u00ean tr\u1ee5c tung v\u00e0 thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = 2x + \\dfrac{3}{4} $. ","select":["A. $M\\left(0; \\dfrac{3}{4}\\right)$ ","B. $M\\left(\\dfrac{3}{4}; 0 \\right)$","C. $M\\left(2; \\dfrac{3}{4}\\right)$ ","D. $M(0; 2)$ "],"explain":"\u0110i\u1ec3m M n\u1eb1m tr\u00ean tr\u1ee5c tung n\u00ean c\u00f3 ho\u00e0nh \u0111\u1ed9 b\u1eb1ng 0. <br\/> $M(0; y_{M})$ v\u00e0 thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = 2x + \\dfrac{3}{4} $ n\u00ean ta c\u00f3: <br\/> $y_{M} = 2.0 + \\dfrac{3}{4} = \\dfrac{3}{4} $ <br\/> V\u1eady t\u1ecda \u0111\u1ed9 \u0111i\u1ec3m M l\u00e0 $M\\left(0; \\dfrac{3}{4}\\right)$ <br\/><br\/><span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 A.<\/span> ","column":2}]}],"id_ques":792},{"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":" Trong nh\u1eefng \u0111i\u1ec3m sau, \u0111i\u1ec3m n\u00e0o thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = 2x - 1 $ ","select":["A. $(0; 1)$ ","B. $(2; 3) $","C. $(1; -1)$ ","D. $(-1; 1)$ "],"explain":" A. Thay $x = 0 $ v\u00e0o $y = 2x - 1 $ ta \u0111\u01b0\u1ee3c $y = 2.0 - 1 = -1 \\neq 1 $ <br\/> $\\Rightarrow $ \u0111i\u1ec3m A(0; 1) kh\u00f4ng thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 y = 2x - 1 <br\/> B. Thay $x = 2$ v\u00e0o $y = 2x - 1 $ ta \u0111\u01b0\u1ee3c $y = 2.2 - 1 = 3 $ <br\/>$\\Rightarrow $ \u0111i\u1ec3m B(2; 3) thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 y = 2x - 1 <br\/> Ta th\u1ea5y \u0111i\u1ec3m C, D kh\u00f4ng thu\u1ed9c \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 n\u00f3i tr\u00ean. <br\/><br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 B. <\/span><br\/>","column":2}]}],"id_ques":793},{"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":[[["-2"]]],"list":[{"point":5,"width":50,"type_input":"","input_hint":["frac"],"ques":"Bi\u1ebft \u0111i\u1ec3m A(a; 9) thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = -4,5x.$ T\u00ecm gi\u00e1 tr\u1ecb c\u1ee7a a? <br\/> <b> \u0110\u00e1p s\u1ed1: <\/b>$a =$ _input_ ","explain":" \u0110i\u1ec3m A(a; 9) thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = -4,5x $ n\u00ean ta c\u00f3: <br\/> $9 = -4,5.a \\Rightarrow a = \\dfrac{-9}{4,5} = -2 $ <br\/> Suy ra t\u1ecda \u0111\u1ed9 \u0111i\u1ec3m A l\u00e0 $A(-2; 9)$"}]}],"id_ques":794},{"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":" T\u00ednh s\u1ed1 k bi\u1ebft \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = (k-1)x $ \u0111i qua \u0111i\u1ec3m $N(6; -4)$ ","select":["A. $\\dfrac{4}{3} $","B. $\\dfrac{2}{3} $","C. $\\dfrac{1}{3} $","D. $\\dfrac{5}{3} $ "],"explain":" \u0110\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = (k-1)x $ \u0111i qua \u0111i\u1ec3m $N(6; -4)$ <br\/> Thay $x = 6; y = -4$ v\u00e0o h\u00e0m s\u1ed1 $y = (k-1)x $ ta \u0111\u01b0\u1ee3c: <br\/> $-4 = (k -1).6 \\\\ \\Rightarrow k - 1 = \\dfrac{-4}{6} = \\dfrac{-2}{3} \\\\ \\Rightarrow k = \\dfrac{-2}{3} + 1 = \\dfrac{-2}{3} + \\dfrac{3}{3} = \\dfrac{1}{3} $ <br\/> V\u1eady $k = \\dfrac{1}{3} $<br\/><br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 C. <\/span><br\/>","column":4}]}],"id_ques":795},{"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":"Cho h\u00e0m s\u1ed1 y = ax + 3. T\u00ecm h\u1ec7 s\u1ed1 a bi\u1ebft r\u1eb1ng \u0111i\u1ec3m $M(-1; -2)$ thu\u1ed9c \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 ","select":["A. $2$","B. $-5$ ","C. $1 $","D. $5 $ "],"explain":"\u0110i\u1ec3m $M(-1; -2)$ thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 y = ax + 3. <br\/> Thay $x = -1; y = -2$ v\u00e0o h\u00e0m s\u1ed1 y = ax + 3, ta \u0111\u01b0\u1ee3c: <br\/> $-2 = a.(-1) + 3 \\\\ \\Leftrightarrow -2 - 3 = -a \\\\ \\Leftrightarrow -5 = -a \\\\ \\Rightarrow a = 5 $ <br\/> V\u1eady h\u1ec7 s\u1ed1 a b\u1eb1ng 5. <br\/><br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 D. <\/span><br\/>","column":4}]}],"id_ques":796},{"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":"\u0110i\u1ec3m n\u00e0o trong c\u00e1c \u0111i\u1ec3m sau kh\u00f4ng thu\u1ed9c \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = -2x?$ ","select":["A. $A(1; -2)$","B. $B(2; -4) $","C. $C\\left(\\dfrac{1}{2}; -1 \\right) $ ","D. $D\\left(\\dfrac{1}{4}; -1 \\right) $ "],"explain":" A. Thay $x = 1 $ v\u00e0o $y = -2x $ ta \u0111\u01b0\u1ee3c $y = -2.1 = -2 $ <br\/> $\\Rightarrow $ \u0111i\u1ec3m $A(1; -2)$ thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 y = -2x <br\/> B. Thay $x = 2 $ v\u00e0o $y = -2x $ ta \u0111\u01b0\u1ee3c $y = -2.2 = -4 $ <br\/> $\\Rightarrow $ \u0111i\u1ec3m $B(2; -4)$ thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 y = -2x <br\/> C. Thay $x = \\dfrac{1}{2} $ v\u00e0o $y = -2x $ ta \u0111\u01b0\u1ee3c $y = -2.\\dfrac{1}{2} = -1 $ <br\/> $\\Rightarrow $ \u0111i\u1ec3m $C\\left(\\dfrac{1}{2}; -1 \\right) $ thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 y = -2x <br\/> D. Thay $x = \\dfrac{1}{4} $ v\u00e0o $y = -2x $ ta \u0111\u01b0\u1ee3c $y = -2.\\dfrac{1}{4} = \\dfrac{-1}{2} \\neq -1 $ <br\/> $\\Rightarrow $ \u0111i\u1ec3m $D\\left(\\dfrac{1}{4}; -1 \\right) $ kh\u00f4ng thu\u1ed9c \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = -2x$ <br\/><br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 D. <\/span><br\/>","column":2}]}],"id_ques":797},{"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":"\u0110\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 n\u00e0o trong c\u00e1c h\u00e0m s\u1ed1 sau \u0111i qua g\u1ed1c t\u1ecda \u0111\u1ed9 O v\u00e0 \u0111i\u1ec3m $A(2; -6)?$ ","select":["A. $y = -2x $","B. $y = -3x $ ","C. $y = -4x $ ","D. $y = 3x $ "],"explain":" T\u1ea5t c\u1ea3 4 \u0111\u1ed3 th\u1ecb tr\u00ean \u0111\u1ec1u \u0111i qua g\u1ed1c t\u1ecda \u0111\u1ed9 O(0; 0) <br\/> \u0110i\u1ec3m $A(2; -6)$ kh\u00f4ng thu\u1ed9c \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = -2x$ v\u00ec $-6 \\neq -2.2 $ <br\/> \u0110i\u1ec3m $A(2; -6)$ thu\u1ed9c \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = -3x $ v\u00ec $-6 = -3.2 $ <br\/> T\u01b0\u01a1ng t\u1ef1 \u0111i\u1ec3m $A(2; -6)$ kh\u00f4ng thu\u1ed9c \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 $y = -4x$ v\u00e0 $y = 3x$<br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 B. <\/span><br\/>","column":2}]}],"id_ques":798},{"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":"\u0110\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = f(x) $ l\u00e0 m\u1ed9t \u0111\u01b0\u1eddng th\u1eb3ng \u0111\u01b0\u1ee3c cho \u1edf h\u00ecnh d\u01b0\u1edbi. H\u00e0m s\u1ed1 \u0111\u00f3 \u0111\u01b0\u1ee3c cho b\u1edfi c\u00f4ng th\u1ee9c n\u00e0o? <br\/><br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai17/lv2/img\/D7B17-25.png' \/><\/center> ","select":["A. $y = \\dfrac{1}{3} x $","B. $y = \\dfrac{-1}{3} x $ ","C. $y = -x $ ","D. $y = -3x $ "],"explain":"\u0110\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $y = f(x) $ l\u00e0 m\u1ed9t \u0111\u01b0\u1eddng th\u1eb3ng \u0111i qua g\u1ed1c t\u1ecda \u0111\u1ed9 n\u00ean h\u00e0m s\u1ed1 $y = f(x) $ c\u00f3 d\u1ea1ng $y = ax $ <br\/> V\u00ec \u0111\u1ed3 th\u1ecb \u0111i qua \u0111i\u1ec3m (3; -1) n\u00ean $x = 3; y = -1 $ <br\/> Thay v\u00e0o c\u00f4ng th\u1ee9c $y = ax $ ta c\u00f3: $-1 = a.3 \\Rightarrow a = \\dfrac{-1}{3} $ <br\/> V\u1eady h\u00e0m s\u1ed1 \u0111\u01b0\u1ee3c cho b\u1edfi c\u00f4ng th\u1ee9c $y = \\dfrac{-1}{3} x $ <br\/><br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 B. <\/span><br\/>","column":2}]}],"id_ques":799},{"time":9,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["3"]]],"list":[{"point":5,"width":20,"content":"","type_input":"","ques":"Bi\u1ebft r\u1eb1ng \u0111\u1ed3 th\u1ecb c\u1ee7a h\u00e0m s\u1ed1 y = f(x) l\u00e0 \u0111o\u1ea1n th\u1eb3ng AB nh\u01b0 h\u00ecnh v\u1ebd sau: <br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/daiso/bai17/lv2/img\/D7B17-26.png' \/><\/center> <br\/> D\u1ef1a v\u00e0o \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 $f(3) = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} $ ","explain":"V\u1edbi x = 3 th\u00ec y = 3, suy ra f(3) = 3 <br\/> <span class='basic_pink'> V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n l\u00e0 3<\/span>"}]}],"id_ques":800}],"lesson":{"save":0,"level":2}}