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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Đăng bài 08-05-12 03:02 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 08-05-12 03:00 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 08-05-12 02:57 PM
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Đăng bài 27-04-12 08:47 AM
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Đăng bài 27-04-12 08:33 AM
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