Chú ý: Để đảm bảo quyền lợi và bảo vệ tài khoản của mình
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HomeLớp 8Toán lớp 8 - Sách Kết nối tri thứcBài 23. Phép cộng và phép trừ phân thức đại sốBài tập nâng cao
{"common":{"save":0,"post_id":"6629","level":3,"total":10,"point":10,"point_extra":0},"segment":[{"id":"6471","post_id":"6629","mon_id":"1158921","chapter_id":"1158930","question":"<p>Rút g\u1ecdn bi\u1ec3u th\u1ee9c <span class=\"math-tex\">$\\dfrac{5}{x-2}+\\dfrac{3}{3-x}+\\dfrac{5}{2-x}-\\dfrac{x}{3-x}$<\/span> ta \u0111\u01b0\u1ee3c <\/p>","options":["<strong>A.<\/strong> 1","<strong>B.<\/strong> 0","<strong>C.<\/strong> x + 1","<strong>D.<\/strong> x"],"correct":"1","level":"3","hint":"","answer":"<p><span class=\"math-tex\">$\\dfrac{5}{x-2}+\\dfrac{3}{3-x}+\\dfrac{5}{2-x}-\\dfrac{x}{3-x}$<\/span><\/p><p>= <span class=\"math-tex\">$\\dfrac{5}{x-2}+\\dfrac{5}{2-x}+\\dfrac{3}{3-x}-\\dfrac{x}{3-x}$<\/span> <\/p><p>= <span class=\"math-tex\">$\\dfrac{5}{x-2}-\\dfrac{5}{x-2}+\\dfrac{3-x}{3-x}$<\/span><\/p><p>= 0 + 1<\/p><p>= 1<\/p><p>\u0110áp án \u0111úng là <span style=\"color:#16a085;\"><strong>A.<\/strong> 1.<\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2023-08-26 22:23:59","option_type":"txt","len":0},{"id":"6474","post_id":"6629","mon_id":"1158921","chapter_id":"1158930","question":"<p>Rút g\u1ecdn bi\u1ec3u th\u1ee9c <span class=\"math-tex\">$\\dfrac{1}{x^2+3x+2}+\\dfrac{1}{x^2+5x+6}+\\dfrac{1}{x^2+7x+12}$<\/span> ta \u0111\u01b0\u1ee3c <\/p>","options":["<strong>A.<\/strong> 0","<strong>B.<\/strong> 1","<strong>C.<\/strong> <span class=\"math-tex\">$\\dfrac{5}{(x+1)(x+4)}$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$\\dfrac{3}{(x+1)(x+4)}$<\/span>"],"correct":"4","level":"3","hint":"<p>Chú ý tính ch\u1ea5t <span class=\"math-tex\">$\\dfrac{k}{n.(n+k)}=\\dfrac{1}{n}-\\dfrac{1}{n+k}$<\/span>.<\/p>","answer":"<p><span class=\"math-tex\">$\\dfrac{1}{x^2+3x+2}+\\dfrac{1}{x^2+5x+6}+\\dfrac{1}{x^2+7x+12}$<\/span><\/p><p>= <span class=\"math-tex\">$\\dfrac{1}{(x+1)(x+2)}+\\dfrac{1}{(x+2)(x+3)}+\\dfrac{1}{(x+3)(x+4)}$<\/span><\/p><p>= <span class=\"math-tex\">$\\dfrac{1}{x+1}-\\dfrac{1}{x+2}+\\dfrac{1}{x+2}-\\dfrac{1}{x+3}+\\dfrac{1}{x+3}-\\dfrac{1}{x+4}$<\/span><\/p><p>= <span class=\"math-tex\">$\\dfrac{1}{x+1}-\\dfrac{1}{x+4}$<\/span><\/p><p>= <span class=\"math-tex\">$\\dfrac{x+4-x-1}{(x+1)(x+4)}$<\/span><\/p><p>= <span class=\"math-tex\">$\\dfrac{3}{(x+1)(x+4)}$<\/span><\/p><p>\u0110áp án \u0111úng là <span style=\"color:#16a085;\"> <strong>D.<\/strong> <span class=\"math-tex\">$\\dfrac{3}{(x+1)(x+4)}$<\/span> .<\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2023-08-26 22:33:02","option_type":"math","len":0},{"id":"6476","post_id":"6629","mon_id":"1158921","chapter_id":"1158930","question":"<p>Rút g\u1ecdn bi\u1ec3u th\u1ee9c <span class=\"math-tex\">$\\dfrac{2}{x^2-8x+15}+\\dfrac{2}{x^2-4x+3}+\\dfrac{2}{x^2-1}$<\/span> là<\/p>","options":["<strong>A.<\/strong> 1","<strong>B.<\/strong> <span class=\"math-tex\">$\\dfrac{6}{(x-5)(x+1)}$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$\\dfrac{2}{(x-5)(x+1)}$<\/span>","<strong>D.<\/strong> 2"],"correct":"2","level":"3","hint":"<p>Chú ý tính ch\u1ea5t <span class=\"math-tex\">$\\dfrac{k}{n.(n+k)}=\\dfrac{1}{n}-\\dfrac{1}{n+k}$<\/span> .<\/p>","answer":"<p><span class=\"math-tex\">$\\dfrac{2}{x^2-8x+15}+\\dfrac{2}{x^2-4x+3}+\\dfrac{2}{x^2-1}$<\/span><\/p><p>= <span class=\"math-tex\">$\\dfrac{2}{(x-5)(x-3)}+\\dfrac{2}{(x-3)(x-1)}+\\dfrac{2}{(x-1)(x+1)}$<\/span><\/p><p>= <span class=\"math-tex\">$\\dfrac{1}{x-5}-\\dfrac{1}{x-3}+\\dfrac{1}{x-3}-\\dfrac{1}{x-1}+\\dfrac{1}{x-1}-\\dfrac{1}{x+1}$<\/span><\/p><p>= <span class=\"math-tex\">$\\dfrac{1}{x-5}-\\dfrac{1}{x+1}$<\/span> <\/p><p>= <span class=\"math-tex\">$\\dfrac{x+1-x+5}{(x-5)(x+1)}$<\/span><\/p><p>= <span class=\"math-tex\">$\\dfrac{6}{(x-5)(x+1)}$<\/span><\/p><p>\u0110áp án \u0111úng là <span style=\"color:#16a085;\"><strong>B.<\/strong> <span class=\"math-tex\">$\\dfrac{6}{(x-5)(x+1)}$<\/span> .<\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2023-08-26 22:39:11","option_type":"math","len":0}]}