\(x=\dfrac{\sqrt{75}+\sqrt{12}}{\sqrt{147}-\sqrt{48}}=\dfrac{5\sqrt{3}+2\sqrt{3}}{7\sqrt{3}-4\sqrt{3}}=\dfrac{7\sqrt{3}}{3\sqrt{3}}=\dfrac{7}{3}\Rightarrow3x=7\)
Vậy:....
\(x=\dfrac{\sqrt{75}+\sqrt{12}}{\sqrt{147}-\sqrt{48}}=\dfrac{5\sqrt{3}+2\sqrt{3}}{7\sqrt{3}-4\sqrt{3}}=\dfrac{7\sqrt{3}}{3\sqrt{3}}=\dfrac{7}{3}\\ \Leftrightarrow3x=7\left(đfcm\right)\)
Ta có \(x=\dfrac{\sqrt{75}+\sqrt{12}}{\sqrt{147}-\sqrt{48}}=\dfrac{\sqrt{3}\left(\sqrt{25}+\sqrt{4}\right)}{\sqrt{3}\left(\sqrt{49}-\sqrt{16}\right)}=\dfrac{5+2}{7-4}=\dfrac{10}{3}\)
\(\Rightarrow3x=\dfrac{3.10}{3}=10\) \(\Rightarrow3x\) là một số nguyên
