A. \(\left(1 ; \frac{2\sqrt{3}-\sqrt{3}}{3}\right)\)
B. \(\left(1 ; \frac{\sqrt{6}-\sqrt{3}}{3}\right)\)
C. \(\left(1 ; \frac{\sqrt{6}+\sqrt{3}}{3}\right)\)
D. \(\left(\frac{\sqrt{6}}{6} ;-\frac{\sqrt{2}}{2}\right)\)
D
\(\begin{aligned} &\left\{\begin{array}{l} 5 x \sqrt{3}+y=2 \sqrt{2} \\ x \sqrt{6}-y \sqrt{2}=2 \end{array} \Leftrightarrow\left\{\begin{array}{l} 5 x \sqrt{6}+y \sqrt{2}=4 \\ x \sqrt{6}-y \sqrt{2}=2 \end{array} \Leftrightarrow\left\{\begin{array}{l} 6 x \sqrt{6}=6 \\ x \sqrt{6}-y \sqrt{2}=2 \end{array}\right.\right.\right.\\ &\Leftrightarrow\left\{\begin{array}{l} x=\frac{1}{\sqrt{6}} \\ \frac{1}{\sqrt{6}} \cdot \sqrt{6}-y \sqrt{2}=2 \end{array} \Leftrightarrow\left\{\begin{array}{l} x=\frac{1}{\sqrt{6}} \\ 1-y \sqrt{2}=2 \end{array}\left\{\begin{array}{l} x=\frac{1}{\sqrt{6}} \\ y \sqrt{2}=-1 \end{array} \Leftrightarrow\left\{\begin{array}{l} x=\frac{\sqrt{6}}{6} \\ y=-\frac{\sqrt{2}}{2} \end{array}\right.\right.\right.\right.\\ &\text { Vậy hệ phương trình có nghiệm duy nhất }(x ; y)=\left(\frac{\sqrt{6}}{6} ;-\frac{\sqrt{2}}{2}\right) \end{aligned}\)
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