Bất phương trình bậc nhất một ẩn

Home Lớp 9 Toán lớp 9 - Sách Kết nối tri thức Bài 6. Bất phương trình bậc nhất một ẩnBài tập trung bình

{"common":{"save":0,"post_id":"7791","level":2,"total":10,"point":10,"point_extra":0},"segment":[{"id":"7335","post_id":"7791","mon_id":"1159278","chapter_id":"1159282","question":"Tìm giá tr\u1ecb c\u1ee7a x sao cho giá tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c 10x + 15 không âm.<\/p>","options":["A.<\/strong> $x\\le \\dfrac{3}{2}$<\/span>","B.<\/strong> $x\\le -\\dfrac{3}{2}$<\/span>","C.<\/strong> $x\\ge \\dfrac{3}{2}$<\/span>","D.<\/strong> $x\\ge -\\dfrac{3}{2}$<\/span>"],"correct":"4","level":"2","hint":"","answer":"Ch\u1ecdn D.<\/strong> $x\\ge -\\dfrac{3}{2}$<\/span><\/span><\/p>\u0110\u1ec3 10x + 15 không âm hay <\/p>10x + 15 ≥ 0<\/p>10x ≥ – 15<\/p>suy ra $x\\ge -\\dfrac{3}{2}$<\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"127","test":"0","date":"2024-10-06 08:32:02","option_type":"math","len":0},{"id":"7337","post_id":"7791","mon_id":"1159278","chapter_id":"1159282","question":"Cho l\u1eddi gi\u1ea3i bài toán tìm nghi\u1ec7m c\u1ee7a b\u1ea5t ph\u01b0\u01a1ng trình sau: <\/p>Gi\u1ea3i b\u1ea5t ph\u01b0\u01a1ng trình: –2x > 23<\/span><\/p>Ta có: –2x > 23 hay x > 23 + 2 hay x > 25.<\/span><\/p>V\u1eady nghi\u1ec7m c\u1ee7a b\u1ea5t ph\u01b0\u01a1ng trình là x > 25.<\/span><\/p>Hãy ki\u1ec3m tra xem l\u1eddi gi\u1ea3i trên \u0111úng hay sai? N\u1ebfu sai thì sai t\u1eeb b\u01b0\u1edbc nào?<\/p>","options":["A.<\/strong> L\u1eddi gi\u1ea3i sai t\u1eeb b\u01b0\u1edbc x > 23 + 2.","B.<\/strong> L\u1eddi gi\u1ea3i sai t\u1eeb b\u01b0\u1edbc x > 25.","C.<\/strong> L\u1eddi gi\u1ea3i sai \u1edf b\u01b0\u1edbc k\u1ebft lu\u1eadn.","D.<\/strong> L\u1eddi gi\u1ea3i \u0111úng."],"correct":"1","level":"2","hint":"","answer":"Ch\u1ecdn A.<\/strong> L\u1eddi gi\u1ea3i sai t\u1eeb b\u01b0\u1edbc x > 23 + 2.<\/span><\/p>Sai l\u1ea7m c\u1ee7a l\u1eddi gi\u1ea3i xu\u1ea5t hi\u1ec7n t\u1eeb b\u01b0\u1edbc \u0111\u1ea7u tiên. <\/p>Ta ph\u1ea3i chia hai v\u1ebf c\u1ee7a b\u1ea5t ph\u01b0\u01a1ng trình cho –2.<\/p>L\u1eddi gi\u1ea3i \u0111úng là:<\/p>Ta có: –2x > 23 hay (–2x) : (–2) < 23 : (–2) suy ra x < $\\dfrac{-23}{2}$<\/span>.<\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"127","test":"0","date":"2024-10-06 08:37:27","option_type":"txt","len":2},{"id":"7340","post_id":"7791","mon_id":"1159278","chapter_id":"1159282","question":"Cho l\u1eddi gi\u1ea3i bài toán tìm nghi\u1ec7m c\u1ee7a b\u1ea5t ph\u01b0\u01a1ng trình sau: <\/p>Gi\u1ea3i b\u1ea5t ph\u01b0\u01a1ng trình –4x > 16.<\/span><\/p>Ta có: –4x > 16 hay <\/span>–4x : (–4) > 16 : (–4) <\/span>suy ra x  < –4.<\/span><\/p>V\u1eady nghi\u1ec7m c\u1ee7a b\u1ea5t ph\u01b0\u01a1ng trình là x  < –4.<\/span><\/p>Hãy ki\u1ec3m tra xem l\u1eddi gi\u1ea3i trên \u0111úng hay sai? N\u1ebfu sai thì sai t\u1eeb b\u01b0\u1edbc nào?<\/p>","options":["A.<\/strong> Sai t\u1eeb b\u01b0\u1edbc –4x : (–4) > 16 : (–4).","B.<\/strong> Sai t\u1eeb b\u01b0\u1edbc x < 4.","C.<\/strong> Sai \u1edf b\u01b0\u1edbc k\u1ebft lu\u1eadn.","D.<\/strong> L\u1eddi gi\u1ea3i \u0111úng."],"correct":"1","level":"2","hint":"","answer":"Ch\u1ecdn A.<\/strong> Sai t\u1eeb b\u01b0\u1edbc –4x : (–4) > 16 : (–4).<\/span><\/p>Sai l\u1ea7m c\u1ee7a l\u1eddi gi\u1ea3i xu\u1ea5t hi\u1ec7n t\u1eeb b\u01b0\u1edbc \u0111\u1ea7u tiên.<\/p>Khi ta chia hai v\u1ebf c\u1ee7a b\u1ea5t ph\u01b0\u01a1ng trình v\u1edbi cùng m\u1ed9t s\u1ed1 âm khác 0 ta ph\u1ea3i \u0111\u1ed5i chi\u1ec1u c\u1ee7a b\u1ea5t ph\u01b0\u01a1ng trình.<\/p>L\u1eddi gi\u1ea3i \u0111úng là:<\/p>Ta có: –4x > 16 hay –4x : (–4) < 16 : (–4) suy ra x  < –4.<\/p>V\u1eady nghi\u1ec7m c\u1ee7a b\u1ea5t ph\u01b0\u01a1ng trình là x  < –4.<\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"127","test":"0","date":"2024-10-06 08:43:27","option_type":"txt","len":3}]}