a)\(\sqrt{3x-1}\)\(=2\)
⇔\(\text{3x-1=2}^2\)
⇔\(3x=5\)
⇔\(x=\dfrac{5}{3}\)
b)\(\sqrt{x^2-4x+4}\)\(\text{=3x-1}\)
⇔\(\text{x-2=3x-1}\)
⇔\(-2x=1\)
⇔\(x=\)\(\dfrac{-1}{2}\)
c)\(\sqrt{x}\)=2-x sai đề bài
d)\(\sqrt{x^2+4}\)=\(\sqrt{3x+8}\)
⇔\(x^2\)\(\text{+4=3x+8}\)
⇔\(x^2\)\(-3x-4=0\)
⇔\(\left(x+1\right)\left(x-4\right)=0\)
⇔\(\left[{}\begin{matrix}x=4\\x=-1\end{matrix}\right.\)