{"common":{"save":0,"post_id":"6068","level":1,"total":10,"point":10,"point_extra":0},"segment":[{"id":"5184","mon_id":"1158767","chapter_id":"1158770","post_id":"6068","question":"<p>Ký hi\u1ec7u nào sau \u0111ây dùng \u0111\u1ec3 vi\u1ebft \u0111úng m\u1ec7nh \u0111\u1ec1: “<span style=\"color:#3498db;\">3 là m\u1ed9t s\u1ed1 t\u1ef1 nhiên<\/span>”?<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$3\\subset \\mathbb{N}$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$3\\in\\mathbb{N}$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$3< \\mathbb{N}$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$3\\le \\mathbb{N}$<\/span>"],"correct":"2","level":"1","hint":"","answer":"<p>- \u0110áp án A sai vì kí hi\u1ec7u “<span class=\"math-tex\">$\\subset$<\/span>” ch\u1ec9 dùng cho hai t\u1eadp h\u1ee3p mà \u1edf \u0111ây “3” là m\u1ed9t s\u1ed1.<\/p><p>- Hai \u0111áp án C và D \u0111\u1ec1u sai vì ta không th\u1ec3 so sánh m\u1ed9t s\u1ed1 v\u1edbi t\u1eadp h\u1ee3p.<\/p><p>\u0110áp án <span style=\"color:#16a085;\"><strong>B.<\/strong> <span class=\"math-tex\">$3\\in\\mathbb{N}$<\/span><\/span><\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2022-08-28 01:29:15","option_type":"math","len":0},{"id":"5186","mon_id":"1158767","chapter_id":"1158770","post_id":"6068","question":"<p>Ký hi\u1ec7u nào sau \u0111ây \u0111\u1ec3 ch\u1ec9 <span style=\"color:#3498db;\"><span class=\"math-tex\">$\\sqrt{5}$<\/span> không ph\u1ea3i là m\u1ed9t s\u1ed1 h\u1eefu t\u1ec9<\/span>?<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$\\sqrt{5}\\ne\\mathbb{Q}$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$\\sqrt{5}\\not\\subset \\mathbb{Q}$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$\\sqrt{5}\\notin\\mathbb{Q}$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$\\sqrt{5}\\subset\\mathbb{Q}$<\/span>"],"correct":"3","level":"1","hint":"","answer":"<p>Vì <span class=\"math-tex\">$\\sqrt{5}$<\/span> là m\u1ed9t ph\u1ea7n t\u1eed còn <span class=\"math-tex\">$\\mathbb{Q}$<\/span> là m\u1ed9t t\u1eadp h\u1ee3p nên các \u0111áp án A, B, D \u0111\u1ec1u sai.<\/p><p>\u0110áp án <span style=\"color:#16a085;\"><strong>C.<\/strong> <span class=\"math-tex\">$\\sqrt{5}\\notin\\mathbb{Q}$<\/span><\/span><\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2022-08-28 01:33:37","option_type":"math","len":0},{"id":"5187","mon_id":"1158767","chapter_id":"1158770","post_id":"6068","question":"<p>Cho t\u1eadp h\u1ee3p <span class=\"math-tex\">$M=\\{x+1 | x\\in\\mathbb{N},x\\le5\\}$<\/span>. T\u1eadp h\u1ee3p M là:<\/p>","options":["<strong>A.<\/strong> M = { 1 ; 2 ; 3 ; 4 ; 5 }","<strong>B.<\/strong> M = { 0 ; 1 ; 2 ; 3 ; 4 ; 5 ; 6 }","<strong>C.<\/strong> M = { 0 ; 1 ; 2 ; 3 ; 4 ; 5 }","<strong>D.<\/strong> M = { 1 ; 2 ; 3 ; 4 ; 5 ; 6 }"],"correct":"4","level":"1","hint":"","answer":"<p>Vì <span class=\"math-tex\">$x\\in\\mathbb{N},\\space x\\le5$<\/span> nên <span class=\"math-tex\">$x\\in\\{0;1;2;3;4;5\\}$<\/span>.<\/p><p>Suy ra <span class=\"math-tex\">$x+1\\in\\{1;2;3;4;5;6\\}$<\/span>.<\/p><p>\u0110áp án là <span style=\"color:#16a085;\"><strong>D.<\/strong> M = { 1 ; 2 ; 3 ; 4 ; 5 ; 6 }<\/span><\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2022-08-28 01:42:39","option_type":"txt","len":2}]}
