{"common":{"save":0,"post_id":"6546","level":3,"total":10,"point":10,"point_extra":0},"segment":[{"id":"5887","post_id":"6546","mon_id":"1158921","chapter_id":"1158928","question":"<p>Vi\u1ebft&nbsp;<span class=\"math-tex\">$9-2b^2$<\/span>&nbsp;d\u01b0\u1edbi d\u1ea1ng t&iacute;ch.<\/p>","options":["<strong>A. <\/strong><span class=\"math-tex\">$(3-\\sqrt{2}b)(3+\\sqrt{2}b)$<\/span>","<strong>B. <\/strong><span class=\"math-tex\">$(1-\\sqrt{2}b)(1+\\sqrt{2}b)$<\/span>","<strong>C. <\/strong><span class=\"math-tex\">$(3-b)(3+b)$<\/span>","<strong>D. <\/strong><span class=\"math-tex\">$(3-2b)(3+2b)$<\/span>"],"correct":"1","level":"3","hint":"","answer":"<p><span class=\"math-tex\">$9-2b^2$<\/span>&nbsp;=&nbsp;<span class=\"math-tex\">$3^2-(\\sqrt{2}b)^2$<\/span>&nbsp;=&nbsp;<span class=\"math-tex\">$(3-\\sqrt{2}b)(3+\\sqrt{2}b)$<\/span>&nbsp;<\/p><p>Ch\u1ecdn&nbsp;<span style=\"color:#16a085;\"><strong>A.&nbsp;<\/strong><span class=\"math-tex\">$(3-\\sqrt{2}b)(3+\\sqrt{2}b)$<\/span><\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2023-07-09 01:18:45","option_type":"math","len":0},{"id":"5888","post_id":"6546","mon_id":"1158921","chapter_id":"1158928","question":"<p>T&igrave;m x, bi\u1ebft:&nbsp;<span class=\"math-tex\">$(4-x)^2-(x-1)^2=0$<\/span>.&nbsp;<\/p>","options":["<strong>A. <\/strong><span class=\"math-tex\">$x=\\dfrac{-5}{6}$<\/span>","<strong>B. <\/strong><span class=\"math-tex\">$x=\\dfrac{-5}{2}$<\/span>","<strong>C. <\/strong><span class=\"math-tex\">$x=\\dfrac{1}{6}$<\/span>","<strong>D. <\/strong><span class=\"math-tex\">$x=\\dfrac{5}{2}$<\/span>"],"correct":"4","level":"3","hint":"","answer":"<p><span class=\"math-tex\">$(4-x)^2-(x-1)^2=0$<\/span><\/p><p><span class=\"math-tex\">$\\Leftrightarrow (16-8x+x^2)-(x^2-2x+1)=0$<\/span><\/p><p><span class=\"math-tex\">$\\Leftrightarrow 15-6x=0$<\/span><\/p><p><span class=\"math-tex\">$\\Leftrightarrow x=\\dfrac{5}{2}$<\/span><\/p><p>Ch\u1ecdn&nbsp;<span style=\"color:#16a085;\"><strong>D.&nbsp;<\/strong><span class=\"math-tex\">$x=\\dfrac{5}{2}$<\/span><\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2023-07-09 01:36:39","option_type":"math","len":0},{"id":"5889","post_id":"6546","mon_id":"1158921","chapter_id":"1158928","question":"<p>Vi\u1ebft bi\u1ec3u th\u1ee9c sau th&agrave;nh \u0111a th\u1ee9c: <span class=\"math-tex\">$(x^2-y)(x^2+y)$<\/span>.<\/p>","options":["<strong>A. <\/strong><span class=\"math-tex\">$x^2-y^2$<\/span>","<strong>B. <\/strong><span class=\"math-tex\">$x^4+y^2$<\/span>","<strong>C. <\/strong><span class=\"math-tex\">$x^4-y^2$<\/span>","<strong>D. <\/strong><span class=\"math-tex\">$x^2+y^2$<\/span>"],"correct":"3","level":"3","hint":"","answer":"<p><span class=\"math-tex\">$(x^2-y)(x^2+y)$<\/span>&nbsp;<\/p><p>=&nbsp;<span class=\"math-tex\">$(x^2)^2-y^2$<\/span>&nbsp;<\/p><p>=&nbsp;<span class=\"math-tex\">$x^4-y^2$<\/span><\/p><p>Ch\u1ecdn&nbsp;<span style=\"color:#16a085;\"><strong>C.&nbsp;<\/strong><span class=\"math-tex\">$x^4-y^2$<\/span><\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2023-07-09 01:39:32","option_type":"math","len":0}]}