Giải các hệ : $\begin{array}{l} 1)\,\,\,\left\{ \begin{array}{l} {y^{1 - \frac{2}{5}{{\log }_x}y}} = {x^{\frac{2}{5}}}\\ 1 + {\log _x}\left( {1 - \frac{{3y}}{x}} \right) = {\log _x}4 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(1)\\ 2)\,\,\,\left\{ \begin{array}{l} y.{x^{{{\log }_y}x}} = {x^{\frac{5}{2}}}\\ {\log _4}y.{\log _y}\left( {y - 3x} \right) = 1 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(2) \end{array}$
Đăng bài 08-05-12 03:43 PM
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Giải các hệ : $\begin{array}{l} 1)\,\,\,\left\{ \begin{array}{l} \left( {1 + 2{{\log }_{\left| {xy} \right|}}2} \right).{\log _{x + y}}\left| {xy} \right| = 1\,\,\,\,(1)\\ x - y = 2\sqrt {3\,} \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(2) \end{array} \right.\\ 2)\,\,\,\left\{ \begin{array}{l} {\log _{\left| {xy} \right|}}\left( {x - y} \right) = 1\\ 2{\log _5}\left| {xy} \right|.{\log _{\left| {xy} \right|}}\left( {x + y} \right) = 1 \end{array} \right. \end{array}$
Đăng bài 08-05-12 03:41 PM
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Đăng bài 08-05-12 03:39 PM
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Đăng bài 08-05-12 03:37 PM
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Giải các hệ : $\begin{array}{l} 1)\,\,\,\left\{ \begin{array}{l} x + {2^{y + 1}} = 3\\ 4x + {4^y} = 32 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,3)\,\,\,\left\{ \begin{array}{l} x + {3^{y - 1}} = 2\\ 3x + {9^y} = 18 \end{array} \right.\\ 2)\,\,\left\{ \begin{array}{l} \sqrt y + \log {x^2} = 2\\ y + 4\log x = 28 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,4)\,\,\,\left\{ \begin{array}{l} \sqrt y + 2\log x = 3\\ y - 3\log {x^2} = 1 \end{array} \right. \end{array}$
Đăng bài 08-05-12 03:34 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 08-05-12 03:28 PM
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Giải các hệ phương trình : $\begin{array}{l} 1)\,\,\,\left\{ \begin{array}{l} {9^x}{.3^y} = 81\\ \lg {\left( {x +y } \right)^2} - \lg x = 2\lg 3 \end{array} \right.\,\,\,\,\,\,\,\,(1)\\ 2)\,\,\left\{ \begin{array}{l} {x^{\sqrt y + x}} = {y^{\frac{4}{3}}}\\ {y^{x + \sqrt y }} = {x^{\frac{4}{3}}} \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(2) \end{array}$
Đăng bài 08-05-12 03:25 PM
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Giải các hệ phương trình: $1)\,\,\left\{ \begin{array}{l} xy = 40\\ {x^{\lg y}} = 4 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,2)\,\,\left\{ \ \begin{array}{l} {\log _y}x + {\log _x}y = 2\\ {x^2} + y = 12 \end{array} \right.$
Đăng bài 08-05-12 03:22 PM
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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 08-05-12 03:18 PM
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Giải hệ phương trình : $\left\{ \begin{array}{l} {\log _x}\left( {3x + 2y} \right) = 2\\ {\log _y}\left( {2x + 3y} \right) = 2 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(1)$
Đăng bài 08-05-12 03:16 PM
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Giải các hệ : $1)\,\,\,\left\{ \begin{array}{l} {\log _2}xy = 5\\ {\log _{\frac{1}{2}}}\frac{x}{y} = 1 \end{array} \right.\,\,\,\,\,(1)\,\,\,\,\,\,\,\,\,\,\,\,2)\,\,\,\,\left\{ \begin{array}{l} xy = 64\\ {\log _x}y = 5 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(2)$
Đăng bài 08-05-12 03:14 PM
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Giải các hệ phương trình : $\begin{array}{l} 1)\,\,\left\{ \begin{array}{l} {\log _2}\left( {{x^2} + {y^2}} \right) = 5\\ 2{\log _4}x + {\log _2}y = 4 \end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,3)\,\,\,\left\{ \begin{array}{l} {3^{\lg x}} = {4^{\lg y}}\\ {\left( {4x} \right)^{\lg 4}} = {\left( {3y} \right)^{\lg 3}} \end{array} \right.\\ 2)\,\,\left\{ \begin{array}{l} {3^{{x^2} + {y^2}}} = 81\\ {\log _2}x + 2{\log _4}y = 1 \end{array} \right. \end{array}$
Đăng bài 08-05-12 03:12 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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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 08-05-12 03:06 PM
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Giải các hệ : $1)\,\,\,\left\{ \begin{array}{l} \frac{1}{{2\sqrt 3 }} = {\left( {x + y} \right)^{\frac{1}{{x - y}}}}\\ \left( {x + y} \right){.2^{y - x}} = 48 \end{array} \right.\,\,\,\,\,\,\,\,2)\,\,\left\{ \begin{array}{l} {\left| x \right|^y} = 9\\ {\left( {324} \right)^{\frac{1}{y}}} = {2^2} \end{array} \right.$
Đăng bài 08-05-12 03:03 PM
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