Đăng bài 25-04-12 03:41 PM
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Đăng bài 14-05-12 08:35 AM
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Đăng bài 14-05-12 08:34 AM
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Đăng bài 05-06-12 11:40 AM
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Đăng bài 14-05-12 02:02 PM
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Đăng bài 27-04-12 08:47 AM
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Đăng bài 02-06-12 08:33 AM
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Đăng bài 11-05-12 10:55 AM
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Giải các hệ phương trình: $\begin{array}{l} 1)\,\,\,\left\{ \begin{array}{l} {\log _{xy}}\left( {x - y} \right) = 1\\ {\log _{xy}}\left( {x + y} \right) = 0 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(1)\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,3)\,\,\,\left\{ \begin{array}{l} {\log _x}y = 2\\ {\log _{x + 1}}\left( {y + 23} \right) = 3 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,(3)\\ 2)\,\,\left\{ \begin{array}{l} y = 1 + {\log _4}x\\ {x^y} = 4096 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(2) \end{array}$
Đăng bài 26-04-12 04:13 PM
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Đăng bài 26-04-12 05:03 PM
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Giải các hệ : $\begin{array}{l} 1)\,\,\,\left\{ \begin{array}{l} {\log _4}x + {\log _4}y = 1 + {\log _4}9\\ x + y - 20 = 0 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(1)\\ 2)\,\,\left\{ \begin{array}{l} {\log _x}y + {\log _y}x = 2\\ {x^2} - y = 20 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(2)\\ 3)\,\,\,\left\{ \begin{array}{l} {3^{ - x}}{.2^y} = 1152\\ {\log _{\sqrt 5 }}\left( {x + y} \right) = 2 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(3) \end{array}$
Đăng bài 08-05-12 03:11 PM
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Giải các hệ phương trình: $\begin{array}{l} 1)\,\,\,\left\{ \begin{array}{l} {x^{x + y}} = {y^{12}}\\ {y^{x + y}} = {x^3} \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(x,y > 0)\\ 2)\,\,\,\left\{ \begin{array}{l} {\log _2}\left( {x + y} \right) - {\log _3}\left( {x - y} \right) = 1\\ {x^2} - {y^2} = 1 \end{array} \right. \end{array}$
Đăng bài 26-04-12 04:25 PM
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Tìm $x, y$ đồng thời thỏa mãn các điều kiện: $\begin{array}{l} x + y = 2\sqrt 3 \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(1)\\ {\log _3}\left( {x.y} \right) = 1\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(2) \end{array}$
Đăng bài 26-04-12 04:00 PM
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Giải các hệ phương trình : $1)\,\,\left\{ \begin{array}{l} xy = 40\\ {x^{\log y}} = 4 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,2)\,\,\left\{ \begin{array}{l} {\log _y}x + {\log _x}y = 2\\ {x^2} + y = 12 \end{array} \right.$
Đăng bài 26-04-12 04:19 PM
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Đăng bài 29-05-12 09:28 AM
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