{"common":{"save":0,"post_id":"7534","level":3,"total":10,"point":10,"point_extra":0},"segment":[{"id":"5445","post_id":"7534","mon_id":"1159285","chapter_id":"1159288","question":"<p>Cho hàm s\u1ed1 <span class=\"math-tex\">$y=\\dfrac{x+1}{x-3}$<\/span> có \u0111\u1ed3 th\u1ecb (C) và các \u0111\u01b0\u1eddng th\u1eb3ng <span class=\"math-tex\">$(d_1):y=2x$<\/span>, <span class=\"math-tex\">$(d_2):y=2x-2$<\/span>, <span class=\"math-tex\">$(d_3):y=3x+3$<\/span>, <span class=\"math-tex\">$(d_4):y=-x+3$<\/span>. H\u1ecfi có bao nhiêu \u0111\u01b0\u1eddng th\u1eb3ng trong b\u1ed1n \u0111\u01b0\u1eddng th\u1eb3ng <span class=\"math-tex\">$d_1,d_2,d_3,d_4$<\/span> \u0111i qua giao \u0111i\u1ec3m c\u1ee7a (C) và tr\u1ee5c hoành?<\/p>","options":["<strong>A.<\/strong> 1","<strong>B.<\/strong> 2","<strong>C.<\/strong> 3","<strong>D.<\/strong> 4"],"correct":"1","level":"3","hint":"<p>Tìm to\u1ea1 \u0111\u1ed9 giao \u0111i\u1ec3m c\u1ee7a \u0111\u1ed3 th\u1ecb hàm s\u1ed1 v\u1edbi tr\u1ee5c hoành là \u0111i\u1ec3m M(<span class=\"math-tex\">$x_0$<\/span> ; <span class=\"math-tex\">$y_0$<\/span>).<br \/>Ki\u1ec3m tra M thu\u1ed9c \u0111\u01b0\u1eddng th\u1eb3ng nào.<\/p>","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>A.<\/strong> 1.<\/span><\/p><p>Ta có (C) c\u1eaft tr\u1ee5c hoành y = 0 t\u1ea1i \u0111i\u1ec3m M(–1 ; 0).<\/p><p>Trong các \u0111\u01b0\u1eddng th\u1eb3ng <span class=\"math-tex\">$d_1,d_2,d_3,d_4$<\/span> ch\u1ec9 có M ∈ <span class=\"math-tex\">$d_3$<\/span>, có ngh\u0129a là có 1 \u0111\u01b0\u1eddng th\u1eb3ng \u0111i qua M(–1 ; 0).<\/p><p>.<\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2024-07-07 03:52:32","option_type":"txt","len":0},{"id":"5447","post_id":"7534","mon_id":"1159285","chapter_id":"1159288","question":"<p>Tìm t\u1ea5t c\u1ea3 các giá tr\u1ecb th\u1ef1c c\u1ee7a tham s\u1ed1 m \u0111\u1ec3 \u0111\u1ed3 th\u1ecb hàm s\u1ed1 <span class=\"math-tex\">$y=x^3-3x^2+2$<\/span> (C) c\u1eaft \u0111\u01b0\u1eddng th\u1eb3ng <span class=\"math-tex\">$(d):y=m(x-1)$<\/span> t\u1ea1i ba \u0111i\u1ec3m phân bi\u1ec7t <span class=\"math-tex\">$x_1,x_2,x_3$<\/span>.<\/p>","options":["<strong>A.<\/strong> m > –2","<strong>B.<\/strong> m = –2","<strong>C.<\/strong> m > –3","<strong>D.<\/strong> m = –3"],"correct":"3","level":"3","hint":"<p>Cho hai \u0111\u1ed3 th\u1ecb y = f(x) và y = g(x).<br \/>Gi\u1ea3i ph\u01b0\u01a1ng trình f(x) = g(x).<br \/>S\u1ed1 giao \u0111i\u1ec3m c\u1ee7a (C) và d là s\u1ed1 nghi\u1ec7m c\u1ee7a f(x) = g(x).<\/p>","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>C.<\/strong> m > –3.<\/span><\/p><p>Ph\u01b0\u01a1ng trình hoành \u0111\u1ed9 giao \u0111i\u1ec3m c\u1ee7a (C) và d là<br \/> <span class=\"math-tex\">$x^3-3x^2+2=m(x-1)$<\/span> (1)<br \/>⇔ <span class=\"math-tex\">$x^3-3x^2-mx+m+2=0$<\/span> <br \/>⇔ <span class=\"math-tex\">$(x-1)(x^2-2x-m-2)=0$<\/span><br \/>⇔ x = 1 ho\u1eb7c <span class=\"math-tex\">$x^2-2x-m-2=0$<\/span> (2)<\/p><p>\u0110\u1ec3 (1) có ba nghi\u1ec7m phân bi\u1ec7t thì (2) có hai nghi\u1ec7m phân bi\u1ec7t khác 1.<br \/>Do \u0111ó <span class=\"math-tex\">$\\Delta^\\prime=1+m+2>0$<\/span> và <span class=\"math-tex\">$1-2-m-2 \\ne 0$<\/span><br \/>⇔ <span class=\"math-tex\">$m > -3$<\/span> và <span class=\"math-tex\">$m \\ne -3$<\/span> ⇔ m > –3.<\/p><p>V\u1eady m > –3.<\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2024-07-07 03:58:34","option_type":"txt","len":2},{"id":"5448","post_id":"7534","mon_id":"1159285","chapter_id":"1159288","question":"<p>\u0110\u01b0\u1eddng th\u1eb3ng d có ph\u01b0\u01a1ng trình y = 2x + 1 c\u1eaft \u0111\u1ed3 th\u1ecb c\u1ee7a hàm s\u1ed1 <span class=\"math-tex\">$y=x^3-x+3$<\/span> t\u1ea1i hai \u0111i\u1ec3m A và B v\u1edbi t\u1ecda \u0111\u1ed9 \u0111\u01b0\u1ee3c kí hi\u1ec7u l\u1ea7n l\u01b0\u1ee3t là <span class=\"math-tex\">$A(x_1;y_1)$<\/span> và <span class=\"math-tex\">$B(x_2;y_2)$<\/span> trong \u0111ó <span class=\"math-tex\">$x_2 < x_1$<\/span>. Tìm <span class=\"math-tex\">$x_2+y_2$<\/span>.<\/p>","options":["<strong>A.<\/strong> –5","<strong>B.<\/strong> –2","<strong>C.<\/strong> 4","<strong>D.<\/strong> 7"],"correct":"1","level":"3","hint":"<p>Cho hai \u0111\u1ed3 th\u1ecb y = f(x) và y = g(x).<br \/>Gi\u1ea3i ph\u01b0\u01a1ng trình f(x) = g(x).<br \/>Tìm hoành \u0111\u1ed9 giao \u0111i\u1ec3m và tung \u0111\u1ed9 giao \u0111i\u1ec3m.<\/p>","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>A.<\/strong> –5.<\/span><\/p><p>Ph\u01b0\u01a1ng trình hoành \u0111\u1ed9 giao \u0111i\u1ec3m c\u1ee7a d và (C) là<\/p><p><span class=\"math-tex\">$x^3-x+3=2x+1$<\/span><\/p><p>⇔ <span class=\"math-tex\">$x^3-3x+2=0$<\/span><\/p><p>⇔ x = –2 ho\u1eb7c x = 1<\/p><p>Suy ra <span class=\"math-tex\">$A(1;3)$<\/span> và <span class=\"math-tex\">$B(-2;-3)$<\/span>. V\u1eady <span class=\"math-tex\">$x_2+y_2=-5$<\/span>.<\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2024-07-07 04:07:35","option_type":"txt","len":1}]}