a, ĐK: \(x\ge0\)
\(\sqrt{2x}-\sqrt{50}=0\)
\(\Leftrightarrow\sqrt{2x}=\sqrt{50}\)
\(\Leftrightarrow2x=50\)
\(\Leftrightarrow x=25\left(tm\right)\)
b, ĐK: \(x\in R\)
\(\sqrt{3x^2}-\sqrt{12}=0\)
\(\Leftrightarrow\sqrt{3x^2}=\sqrt{12}\)
\(\Leftrightarrow3x^2=12\)
\(\Leftrightarrow x=\pm2\)