Chú ý: Để đảm bảo quyền lợi và bảo vệ tài khoản của mình
Bạn hãy xác thực địa chỉ email đăng ký nhé. Chi tiết xem tại đây
Bạn hãy xác thực địa chỉ email đăng ký nhé. Chi tiết xem tại đây
{"common":{"save":0,"post_id":"7100","level":2,"total":10,"point":10,"point_extra":0},"segment":[{"id":"5363","post_id":"7100","mon_id":"1158924","chapter_id":"1159168","question":"<p>Cho a, b, c là các s\u1ed1 th\u1ef1c d\u01b0\u01a1ng th\u1ecfa mãn <span class=\"math-tex\">$\\log_5a=x$<\/span>, <span class=\"math-tex\">$\\log_5b=y$<\/span>, <span class=\"math-tex\">$\\log_5c=z$<\/span>. Giá tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c <span class=\"math-tex\">$E=\\log_\\sqrt{5}\\bigg(\\dfrac{a^3b^2}{\\sqrt{c}}\\bigg)$<\/span> là<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$\\dfrac{3}{2}x+y-\\dfrac{1}{4}z$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$3x+2y-\\dfrac{1}{2}z$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$6x+4y-z$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$\\dfrac{3}{2}x+y+\\dfrac{1}{4}z$<\/span>"],"correct":"3","level":"2","hint":"","answer":"<p><span class=\"math-tex\">$E=\\log_\\sqrt{5}\\bigg(\\dfrac{a^3b^2}{\\sqrt{c}}\\bigg)$<\/span><\/p><p><span class=\"math-tex\">$=2\\log_5\\bigg(\u200b\u200b\\dfrac{a^3b^2}{\\sqrt{c}}\\bigg)$<\/span><\/p><p><span class=\"math-tex\">$=2\\bigg(\\log_5a^3+\\log_5b^2-\\log_5c^\\frac{1}{2}\\bigg)$<\/span><\/p><p><span class=\"math-tex\">$=2\\bigg(3\\log_5a+2\\log_5b-\\dfrac{1}{2}\\log_5c\\bigg)$<\/span><\/p><p><span class=\"math-tex\">$=6\\log_5a+4\\log_5b-\\log_5c$<\/span><\/p><p><span class=\"math-tex\">$=6x+4y-z$<\/span><\/p><p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>C.<\/strong> <span class=\"math-tex\">$6x+4y-z$<\/span>.<\/span><\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2024-03-10 05:30:09","option_type":"math","len":0},{"id":"5366","post_id":"7100","mon_id":"1158924","chapter_id":"1159168","question":"<p>Cho a, b là các s\u1ed1 th\u1ef1c d\u01b0\u01a1ng th\u1ecfa mãn <span class=\"math-tex\">$\\log_2a=3,\\log_2b=7$<\/span>. Giá tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c <span class=\"math-tex\">$F=\\log_{ab}\\bigg(\\dfrac{a^2}{b}\\bigg)$<\/span> là<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$-\\dfrac{1}{10}$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$\\dfrac{1}{10}$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$\\dfrac{3}{7}$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$\\dfrac{7}{3}$<\/span>"],"correct":"1","level":"2","hint":"","answer":"<p><span class=\"math-tex\">$F=\\log_{ab}\\bigg(\\dfrac{a^2}{b}\\bigg)$<\/span><\/p><p><span class=\"math-tex\">$=\\dfrac{\\log_2\\bigg(\\dfrac{a^2}{b}\\bigg)}{\\log_2 ab}$<\/span><\/p><p><span class=\"math-tex\">$=\\dfrac{2\\log_2a-\\log_2b}{\\log_2a+\\log_2b}$<\/span><\/p><p><span class=\"math-tex\">$=\\dfrac{2.3-7}{3+7}$<\/span> <span class=\"math-tex\">$=-\\dfrac{1}{10}$<\/span><\/p><p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>A.<\/strong> <span class=\"math-tex\">$-\\dfrac{1}{10}$<\/span>.<\/span><\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2024-03-31 02:50:13","option_type":"math","len":0},{"id":"5367","post_id":"7100","mon_id":"1158924","chapter_id":"1159168","question":"<p>Cho a, b là các s\u1ed1 th\u1ef1c d\u01b0\u01a1ng th\u1ecfa mãn <span class=\"math-tex\">$\\log_ab=\\dfrac{b}{8},\\log_2a=\\dfrac{16}{b}$<\/span> . Giá tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c G = a + b là<\/p>","options":["<strong>A.<\/strong> 10","<strong>B.<\/strong> 20","<strong>C.<\/strong> 12","<strong>D.<\/strong> 24"],"correct":"2","level":"2","hint":"","answer":"<p>Vì <span class=\"math-tex\">$\\log_ab=\\dfrac{b}{8},\\log_2a=\\dfrac{16}{b}$<\/span> nên <span class=\"math-tex\">$\\log_2a.\\log_ab=\\dfrac{16}{b}.\\dfrac{b}{8}$<\/span> <\/p><p>⇔ <span class=\"math-tex\">$\\log_2b=2$<\/span> ⇔ <span class=\"math-tex\">$b=2^2=4$<\/span>.<\/p><p>Khi \u0111ó <span class=\"math-tex\">$\\log_2a=\\dfrac{16}{b}=\\dfrac{16}{4}=4$<\/span> ⇒ <span class=\"math-tex\">$a=2^4=16$<\/span><\/p><p>Do \u0111ó G = a + b = 16 + 4 = 20.<\/p><p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>B.<\/strong> 20.<\/span><\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2024-03-31 02:55:26","option_type":"txt","len":0}]}