ĐK \(3x+y\ge0;y\ge0\)
PT
<=> \(\left(\sqrt{3x+y}-2\sqrt{y}\right)+y\left(x-y\right)=0\)
<=> \(\frac{3\left(x-y\right)}{\sqrt{3x+y}+2\sqrt{y}}+y\left(x-y\right)=0\)
<=> \(\left[{}\begin{matrix}x=y\\\frac{3}{\sqrt{3x+y}+2\sqrt{y}}+y=0\left(2\right)\end{matrix}\right.\)
Pt (2) vô nghiệm do \(y\ge0\)
x=y
=> \(2\sqrt{x}+x^2=x^2+2\sqrt{x}\)luôn đúng
Vậy PT có nghiệm x=y