{"common":{"save":0,"post_id":"6609","level":3,"total":10,"point":10,"point_extra":0},"segment":[{"id":"6551","post_id":"6609","mon_id":"1158921","chapter_id":"1158930","question":"<p>Th\u1ef1c hi\u1ec7n phép nhân <span class=\"math-tex\">$\\dfrac{x+3}{1-x}.\\dfrac{x}{x+4}.\\dfrac{x-1}{x+3}.\\dfrac{x^2-16}{3x^2}$<\/span><\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$\\dfrac{4+x}{x}$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$\\dfrac{4-x}{3-x}$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$\\dfrac{4-x}{3x}$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$\\dfrac{4x}{3+x}$<\/span>"],"correct":"3","level":"3","hint":"","answer":"<p>Ta có: <span class=\"math-tex\">$\\dfrac{x+3}{1-x}.\\dfrac{x}{x+4}.\\dfrac{x-1}{x+3}.\\dfrac{x^2-16}{3x^2}$<\/span><\/p><p>= <span class=\"math-tex\">$\\dfrac{x+3}{1-x}.\\dfrac{x}{x+4}.\\dfrac{-(1-x)}{x+3}.\\dfrac{(x-4)(x+4)}{3x^2}$<\/span><\/p><p>= <span class=\"math-tex\">$\\dfrac{-(x-4)}{3x}$<\/span><\/p><p>= <span class=\"math-tex\">$\\dfrac{4-x}{3x}$<\/span><\/p><p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>C.<\/strong> <span class=\"math-tex\">$\\dfrac{4-x}{3x}$<\/span><\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2023-08-27 09:45:30","option_type":"math","len":0},{"id":"6553","post_id":"6609","mon_id":"1158921","chapter_id":"1158930","question":"<p>Tìm bi\u1ec3u th\u1ee9c M sao cho <span class=\"math-tex\">$\\dfrac{5x^2}{8-x^3}:M=\\dfrac{20x}{4+2x+x^2}$<\/span>.<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$M=\\dfrac{4x}{2+x}$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$M=\\dfrac{x}{4(2-x)}$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$M=\\dfrac{4x}{5(2+x)}$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$M=\\dfrac{x}{2-x}$<\/span>"],"correct":"2","level":"3","hint":"","answer":"<p>Ta có: <span class=\"math-tex\">$\\dfrac{5x^2}{8-x^3}:M=\\dfrac{20x}{4+2x+x^2}$<\/span><\/p><p>Suy ra <span class=\"math-tex\">$M=\\dfrac{5x^2}{8-x^3}:\\dfrac{20x}{4+2x+x^2}$<\/span><\/p><p> <span class=\"math-tex\">$M=\\dfrac{5x^2}{(2-x)(4+2x+x^2)}.\\dfrac{4+2x+x^2}{20x}$<\/span><\/p><p> <span class=\"math-tex\">$M=\\dfrac{x}{4(2-x)}$<\/span><\/p><p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>B.<\/strong> <span class=\"math-tex\">$M=\\dfrac{x}{4(2-x)}$<\/span><\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2023-08-27 09:50:37","option_type":"math","len":0},{"id":"6556","post_id":"6609","mon_id":"1158921","chapter_id":"1158930","question":"<p>Kh\u1eb3ng \u0111\u1ecbnh nào <strong>sai<\/strong>?<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$\\dfrac{x-1}{x^2+4}.\\dfrac{4+x^2}{x-1}=1$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$\\dfrac{x-1}{x^2-9}.\\dfrac{x^2-9}{1-x}=-1$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$\\dfrac{x-2}{x}.\\dfrac{-3}{3x-6}=\\dfrac{1}{x}$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$\\dfrac{x-2}{x}.\\dfrac{3}{3x-6}=\\dfrac{1}{x}$<\/span>"],"correct":"3","level":"3","hint":"","answer":"<p><strong>A.<\/strong> <span class=\"math-tex\">$\\dfrac{x-1}{x^2+4}.\\dfrac{4+x^2}{x-1}=1$<\/span> (\u0111úng)<\/p><p><strong>B.<\/strong> <span class=\"math-tex\">$\\dfrac{x-1}{x^2-9}.\\dfrac{x^2-9}{1-x}=-1$<\/span> (\u0111úng)<\/p><p><strong>C.<\/strong> <span class=\"math-tex\">$\\dfrac{x-2}{x}.\\dfrac{-3}{3x-6}=\\dfrac{1}{x}$<\/span> (sai vì <span class=\"math-tex\">$\\dfrac{x-2}{x}.\\dfrac{-3}{3x-6}=\\dfrac{-1}{x}$<\/span>)<\/p><p><strong>D.<\/strong> <span class=\"math-tex\">$\\dfrac{x-2}{x}.\\dfrac{3}{3x-6}=\\dfrac{1}{x}$<\/span> (\u0111úng)<\/p><p>Câu <strong>sai <\/strong>là <span style=\"color:#16a085;\"><strong>C.<\/strong> <span class=\"math-tex\">$\\dfrac{x-2}{x}.\\dfrac{-3}{3x-6}=\\dfrac{1}{x}$<\/span><\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2023-08-27 09:56:46","option_type":"math","len":0}]}