Bài 1:
a) \(5\sqrt{27}-3\sqrt{12}+\sqrt{147}-2\sqrt{48}=15\sqrt{3}-6\sqrt{3}+7\sqrt{3}-8\sqrt{3}=8\sqrt{3}\)
b) \(\sqrt{4+2\sqrt{3}}-\dfrac{2}{2+\sqrt{3}}-\sqrt{27}\)
\(=\sqrt{\left(\sqrt{3}+1\right)^2}-\dfrac{2\left(2-\sqrt{3}\right)}{4-3}-3\sqrt{3}\)
\(=\sqrt{3}+1-4+2\sqrt{3}-3\sqrt{3}=-3\)
Bài 2:
a) \(\Rightarrow\sqrt{\left(x-5\right)^2}=6\)
\(\Rightarrow\left|x-5\right|=6\)
\(\Rightarrow\left[{}\begin{matrix}x-5=6\\x-5=-6\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}x=11\\x=-1\end{matrix}\right.\)
b) \(\sqrt{2x-1}+\dfrac{3}{2}\sqrt{8x-4}-\dfrac{2}{5}\sqrt{50x-25}-4=0\left(đk:x\ge\dfrac{1}{2}\right)\)
\(\Rightarrow\sqrt{2x-1}+3\sqrt{2x-1}-2\sqrt{2x-1}=4\)
\(\Rightarrow2\sqrt{2x-1}=4\)
\(\Rightarrow\sqrt{2x-1}=2\Rightarrow2x-1=4\Rightarrow x=\dfrac{5}{2}\)
