Giải các hệ phương trình :
$\begin{array}{l}
1)\,\,\,\left\{ \begin{array}{l}
{9^x}{.3^y} = 81\\
\log {\left( {x +y } \right)^2} - \log x = 2\log 3
\end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,(1)\\
2)\,\,\left\{ \begin{array}{l}
{x^{\sqrt y + x}} = {y^{\frac{4}{3}}}\\
{y^{x + \sqrt y }} = {x^{\frac{4}{3}}}
\end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(2)
\end{array}$
Đăng bài 26-04-12 04:21 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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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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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 26-04-12 04:11 PM
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Giải các hệ phương trình sau:
$1)\,\,\,\left\{ \begin{array}{l}
{\log _2}xy = 5\\
{\log _{\frac{1}{2}}}\frac{x}{y} = 1
\end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(1)\,\,\,\,\,\,\,\,\,\,\,\,2)\,\,\,\,\left\{ \begin{array}{l}
xy = 64\\
{\log _x}y = 5
\end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(2)$
Đăng bài 26-04-12 04:09 PM
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Giải các hệ phương trình:
$\begin{array}{l}
1)\,\,\left\{ \begin{array}{l}
{\log _2}\left( {{x^2} + {y^2}} \right) = 5\\
2{\log _4}x + {\log _2}y = 4
\end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,3)\,\,\,\left\{ \begin{array}{l}
{3^{\log x}} = {4^{\log y}}\\
{\left( {4x} \right)^{\log 4}} = {\left( {3y} \right)^{\log 3}}
\end{array} \right.\\
2)\,\,\left\{ \begin{array}{l}
{3^{{x^2} + {y^2}}} = 81\\
{\log _2}x + 2{\log _4}y = 1
\end{array} \right.
\end{array}$
Đăng bài 26-04-12 04:06 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 26-04-12 04:03 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 :
$1)\,\,\,\left\{ \begin{array}{l}
\frac{1}{{4\sqrt 3 }} = {\left( {x + y} \right)^{\frac{1}{{x - y}}}}\\
\left( {x + y} \right){.2^{y - x}} = 48
\end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,2)\,\,\left\{ \begin{array}{l}
{\left| x \right|^y} = 9\\
{\left( {324} \right)^{\frac{1}{y}}} = {2.9^{\frac{2}{y}}}
\end{array} \right.$
Đăng bài 26-04-12 03:57 PM
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Đăng bài 26-04-12 03:55 PM
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Giải các hệ :
$1)\,\,\,\,\,\,\left\{ \begin{array}{l}
{3^x}{.2^y} = \frac{1}{9}\\
y - x = 2
\end{array} \right.\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,2)\,\,\,\left\{ \begin{array}{l}
{2^y} = {200.5^x}\\
x + y = 1
\end{array} \right.$
Đăng bài 26-04-12 03:50 PM
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Giải các hệ phương trình :
$\begin{array}{l}
1)\,\,\,\left\{ \begin{array}{l}
{y^2} = {4^x} + 8\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(1)\\
{2^{x + 1}} + y + 1 = 0\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,(2)
\end{array} \right.\\
2)\,\,\left\{ \begin{array}{l}
{y^2} = {4^x} + 2\,\\
{2^{x + 1}} + 2y + 1 = 0
\end{array} \right.
\end{array}$
Đăng bài 26-04-12 03:48 PM
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Đăng bài 25-04-12 03:41 PM
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Đăng bài 25-04-12 03:33 PM
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