{"common":{"save":0,"post_id":"7820","level":3,"total":10,"point":10,"point_extra":0},"segment":[{"id":"7673","post_id":"7820","mon_id":"1159278","chapter_id":"1159327","question":"<p>V\u1edbi x = <span class=\"math-tex\">$\\sqrt{26}$<\/span> giá tr\u1ecb bi\u1ec3u th\u1ee9c P = <span class=\"math-tex\">$\\sqrt{x-1}.\\sqrt{x+1}$<\/span> là:<\/p>","options":["<strong>A.<\/strong> P = 15","<strong>B.<\/strong> P = 5","<strong>C.<\/strong> P = <span class=\"math-tex\">$5\\sqrt{2}$<\/span>","<strong>D.<\/strong> P = <span class=\"math-tex\">$5\\sqrt{3}$<\/span>"],"correct":"2","level":"3","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>B.<\/strong> P = 5<\/span><\/p><p>V\u1edbi x = <span class=\"math-tex\">$\\sqrt{26}$<\/span> giá tr\u1ecb bi\u1ec3u th\u1ee9c P = <span class=\"math-tex\">$\\sqrt{x-1}.\\sqrt{x+1}$<\/span> là:<\/p><p>P = <span class=\"math-tex\">$\\sqrt{\\sqrt{26}-1}.\\sqrt{\\sqrt{26}+1}=\\sqrt{(\\sqrt{26}-1)(\\sqrt{26}+1)}=\\sqrt{26-1}=\\sqrt{25}=5$<\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"127","test":"0","date":"2024-10-13 01:18:57","option_type":"math","len":0},{"id":"7675","post_id":"7820","mon_id":"1159278","chapter_id":"1159327","question":"<p>Giá tr\u1ecb c\u1ee7a <span class=\"math-tex\">$\\sqrt{9a^2(b^2+4-4b)}$<\/span> khi a = 2 và b = <span class=\"math-tex\">$-\\sqrt{3}$<\/span>, b\u1eb1ng s\u1ed1 nào sau \u0111ây:<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$6.(\\sqrt{3}+2)$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$-6.(\\sqrt{3}+2)$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$6.(\\sqrt{3}-2)$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$3.(\\sqrt{3}+2)$<\/span>"],"correct":"1","level":"3","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>A.<\/strong> <span class=\"math-tex\">$6.(\\sqrt{3}+2)$<\/span><\/span><\/p><p><span class=\"math-tex\">$\\sqrt{9a^2(b^2+4-4b)}=$<\/span> <span class=\"math-tex\">$\\sqrt{9}.\\sqrt{a^2}.\\sqrt{(b-2)^2}=$<\/span> <span class=\"math-tex\">$3.|a|.|b-2|$<\/span><\/p><p>Giá tr\u1ecb c\u1ee7a <span class=\"math-tex\">$\\sqrt{9a^2(b^2+4-4b)}$<\/span> khi a = 2 và b = <span class=\"math-tex\">$-\\sqrt{3}$<\/span> là:<\/p><p><span class=\"math-tex\">$3.|a|.|b-2|=$<\/span> <span class=\"math-tex\">$3.2.|-\\sqrt{3}-2|=$<\/span><span class=\"math-tex\">$6.(\\sqrt{3}+2)$<\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"127","test":"0","date":"2024-10-13 01:24:50","option_type":"math","len":0},{"id":"7678","post_id":"7820","mon_id":"1159278","chapter_id":"1159327","question":"<p>Tính giá tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c <span class=\"math-tex\">$P=\\dfrac{x-2\\sqrt{x}}{\\sqrt{x}-2}$<\/span> bi\u1ebft 2x – 5 = 7.<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$P=-\\sqrt{6}$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$P=1$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$P=6$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$P=\\sqrt{6}$<\/span>"],"correct":"4","level":"3","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>D.<\/strong> <span class=\"math-tex\">$P=\\sqrt{6}$<\/span><\/span><\/p><p>2x – 5 = 7 suy ra x = 6. Khi \u0111ó thay x = 6 vào P ta \u0111\u01b0\u1ee3c:<\/p><p><span class=\"math-tex\">$P=\\dfrac{6-2\\sqrt{6}}{\\sqrt{6}-2}=\\dfrac{\\sqrt{6}(\\sqrt{6}-2)}{\\sqrt{6}-2}=\\sqrt{6}$<\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"127","test":"0","date":"2024-10-13 01:34:47","option_type":"math","len":0}]}