a: \(\Leftrightarrow\sqrt{3+\sqrt{x}}+2=9\)
\(\Leftrightarrow3+\sqrt{x}=49\)
=>căn x=46
hay x=2116
b: \(\Leftrightarrow2x^2-4x+2=36\)
\(\Leftrightarrow2x^2-4x-34=0\)
hay \(x\in\left\{1+3\sqrt{2};1-3\sqrt{2}\right\}\)
c: \(\Leftrightarrow\sqrt{x-1}-3=0\)
=>x-1=9
hay x=10