{"common":{"save":0,"post_id":"7045","level":1,"total":10,"point":10,"point_extra":0},"segment":[{"id":"4795","post_id":"7045","mon_id":"1158924","chapter_id":"1159147","question":"<p>Cho dãy s\u1ed1 <span class=\"math-tex\">$(u_n)$<\/span> v\u1edbi <span class=\"math-tex\">$u_n=n$<\/span> . Tính <span class=\"math-tex\">$u_5$<\/span> .<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$u_5=-5$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$u_5=5$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$u_5=4$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$u_5=-4$<\/span>"],"correct":"2","level":"1","hint":"","answer":"<p>Ta có <span class=\"math-tex\">$u_5=5$<\/span> .<\/p><p>Ch\u1ecdn <span style=\"color:#16a085;\"> <strong>B.<\/strong> <span class=\"math-tex\">$u_5=5$<\/span> .<\/span><\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2023-12-03 01:32:34","option_type":"math","len":0},{"id":"4796","post_id":"7045","mon_id":"1158924","chapter_id":"1159147","question":"<p>Cho dãy s\u1ed1 <span class=\"math-tex\">$(u_n)$<\/span> v\u1edbi <span class=\"math-tex\">$u_n=\\dfrac{(-1)^n}{n}$<\/span> . Tính <span class=\"math-tex\">$u_{2023}$<\/span> .<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$\\dfrac{1}{2023}$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$-\\dfrac{1}{2023}$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$-2023$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$2023$<\/span>"],"correct":"2","level":"1","hint":"","answer":"<p>Ta có <span class=\"math-tex\">$u_{2023}=\\dfrac{(-1)^{2023}}{2023}=-\\dfrac{1}{2023}$<\/span> .<\/p><p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>B.<\/strong> <span class=\"math-tex\">$-\\dfrac{1}{2023}$<\/span> .<\/span><\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2023-12-03 01:35:56","option_type":"math","len":0},{"id":"4799","post_id":"7045","mon_id":"1158924","chapter_id":"1159147","question":"<p>Cho dãy s\u1ed1 <span class=\"math-tex\">$(u_n)$<\/span> v\u1edbi <span class=\"math-tex\">$u_n=2n+3$<\/span> . Tính <span class=\"math-tex\">$u_7$<\/span> .<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$u_7=14$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$u_7=7$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$u_7=17$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$u_7=3$<\/span>"],"correct":"3","level":"1","hint":"","answer":"<p>Ta có <span class=\"math-tex\">$u_7=2.7+3=17$<\/span> .<\/p><p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>C.<\/strong> <span class=\"math-tex\">$u_7=17$<\/span> .<\/span><\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2023-12-03 01:38:33","option_type":"math","len":0}]}
