{"common":{"save":0,"post_id":"6548","level":2,"total":10,"point":10,"point_extra":0},"segment":[{"id":"5847","post_id":"6548","mon_id":"1158921","chapter_id":"1158928","question":"<p>Khai tri\u1ec3n&nbsp;&nbsp;<span class=\"math-tex\">$\\bigg(x-\\dfrac{1}{2}\\bigg)^3$<\/span>&nbsp; ta \u0111\u01b0\u1ee3c<\/p>","options":["<strong>A.<\/strong> <span class=\"math-tex\">$x^3 + \\dfrac{3}{2}x^2-\\dfrac{3}{4}x+\\dfrac{1}{8}$<\/span>","<strong>B.<\/strong> <span class=\"math-tex\">$x^3 + \\dfrac{3}{4}x^2-\\dfrac{3}{2}x-\\dfrac{1}{8}$<\/span>","<strong>C.<\/strong> <span class=\"math-tex\">$x^3 -\\dfrac{3}{4}x^2-\\dfrac{3}{2}x+\\dfrac{1}{8}$<\/span>","<strong>D.<\/strong> <span class=\"math-tex\">$x^3 -\\dfrac{3}{2}x^2+\\dfrac{3}{4}x-\\dfrac{1}{8}$<\/span>"],"correct":"4","level":"2","hint":"<p>(A&nbsp;&ndash; B)&sup3; = A&sup3;&nbsp;&ndash; 3A&sup2;B + 3AB&sup2;&nbsp;&ndash; B&sup3; .<\/p>","answer":"<p><span class=\"math-tex\">$\\bigg(x-\\dfrac{1}{2}\\bigg)^3$<\/span>&nbsp;=&nbsp;<span class=\"math-tex\">$x^3-3.x^2.\\dfrac{1}{2}+3.x.\\bigg(\\dfrac{1}{2}\\bigg)^2-\\bigg(\\dfrac{1}{2}\\bigg)^3$<\/span>&nbsp;<\/p><p>=&nbsp;<span class=\"math-tex\">$x^3-\\dfrac{3}{2}x^2+\\dfrac{3}{4}x-\\dfrac{1}{8}$<\/span>&nbsp;.<\/p><p>\u0110&aacute;p &aacute;n \u0111&uacute;ng l&agrave;&nbsp; &nbsp;<span style=\"color:#16a085;\"><strong>D.<\/strong>&nbsp;<span class=\"math-tex\">$x^3 -\\dfrac{3}{2}x^2+\\dfrac{3}{4}x-\\dfrac{1}{8}$<\/span>.<\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2023-07-04 14:18:17","option_type":"math","len":0},{"id":"5849","post_id":"6548","mon_id":"1158921","chapter_id":"1158928","question":"<p>Khai tri\u1ec3n&nbsp; (2x + 1)&sup3;&nbsp; ta \u0111\u01b0\u1ee3c<\/p>","options":["<strong>A.<\/strong> 8x&sup3; + 6x&sup2; + 6x + 1","<strong>B.<\/strong> 8x&sup3; + 12x&sup2; + 6x + 1","<strong>C.<\/strong> 8x&sup3; + 12x&sup2; + 12x + 1","<strong>D.<\/strong> 8x&sup3; + 8x&sup2; + 6x + 1"],"correct":"2","level":"2","hint":"<p>(A +&nbsp;B)&sup3; = A&sup3; +&nbsp;3A&sup2;B + 3AB&sup2;&nbsp;+ B&sup3; .<\/p>","answer":"<p>(2x + 1)&sup3; = (2x)&sup3; + 3.(2x)&sup2;.1 + 3.2x.1&sup2; + 1&sup3;<\/p><p>= 8x&sup3; + 12x&sup2; + 6x + 1 .<\/p><p>\u0110&aacute;p &aacute;n \u0111&uacute;ng&nbsp;l&agrave;&nbsp; &nbsp;<span style=\"color:#16a085;\"><strong>B.<\/strong> 8x&sup3; + 12x&sup2; + 6x + 1.<\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2023-07-04 14:21:25","option_type":"txt","len":2},{"id":"5851","post_id":"6548","mon_id":"1158921","chapter_id":"1158928","question":"<p>Khai tri\u1ec3n&nbsp; (3x&nbsp;&ndash; 1)&sup3;&nbsp; ta \u0111\u01b0\u1ee3c<\/p>","options":["<strong>A.<\/strong> 27x&sup3; &ndash; 27x&sup2; + 9x &ndash; 1","<strong>B.<\/strong> 27x&sup3; &ndash; 27x&sup2; &ndash; 9x &ndash; 1","<strong>C.<\/strong> 27x&sup3; &ndash; 9x&sup2; + 9x &ndash; 1","<strong>D.<\/strong> 27x&sup3; + 27x&sup2; + 9x &ndash; 1"],"correct":"1","level":"2","hint":"<p>(A&nbsp;&ndash; B)&sup3; = A&sup3;&nbsp;&ndash; 3A&sup2;B + 3AB&sup2;&nbsp;&ndash; B&sup3;&nbsp;<\/p>","answer":"<p>(3x&nbsp;&ndash; 1)&sup3; = (3x)&sup3;&nbsp;&ndash; 3.(3x)&sup2;.1 + 3.3x.1&sup2;&nbsp;&ndash; 1&sup3;<\/p><p>= 27x&sup3;&nbsp;&ndash; 27x&sup2; + 9x&nbsp;&ndash; 1 .<\/p><p>\u0110&aacute;p &aacute;n \u0111&uacute;ng l&agrave;&nbsp; &nbsp;&nbsp;<span style=\"color:#16a085;\"><strong>A.<\/strong> 27x&sup3;&nbsp;&ndash; 27x&sup2; + 9x&nbsp;&ndash; 1.<\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2023-07-04 14:25:05","option_type":"txt","len":3}]}