1) \(3\sqrt{32}-2\sqrt{75}-4\dfrac{\sqrt{54}}{\sqrt{3}}-3\sqrt{\dfrac{1}{3}}\)
\(=3\sqrt{4^2\cdot2}-2\sqrt{5^2\cdot3}-4\sqrt{\dfrac{54}{3}}-3\dfrac{\sqrt{1}}{\sqrt{3}}\)
\(=3\cdot4\sqrt{2}-2\cdot5\sqrt{3}-4\sqrt{18}-\dfrac{3}{\sqrt{3}}\)
\(=12\sqrt{2}-10\sqrt{3}-4\cdot3\sqrt{2}-\dfrac{\left(\sqrt{3}\right)^2}{\sqrt{3}}\)
\(=12\sqrt{2}-10\sqrt{3}-12\sqrt{2}-\sqrt{3}\)
\(=-11\sqrt{3}\)
2) \(\sqrt{9x}+\sqrt{4x}=18-\sqrt{x}\left(x\ge0\right)\)
\(\Rightarrow3\sqrt{x}+2\sqrt{x}=18-\sqrt{x}\)
\(\Rightarrow3\sqrt{x}+2\sqrt{x}+\sqrt{x}=18\)
\(\Rightarrow6\sqrt{x}=18\)
\(\Rightarrow\sqrt{x}=3\)
\(\Rightarrow x=9\left(tm\right)\)
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