\(x^2-4x-6=2\sqrt{2x^2-8x+12}\)

\(\left(x+4\right)\left(x+1\right)-3\sqrt{x^2+5x+6}\)

\(\sqrt{x-\frac{1}{x}}+\sqrt{1-\frac{1}{x}}=\frac{x-1}{x}\)

\(\sqrt{2x^2+21x-11}-\sqrt{2x^2-9x+4}=\sqrt{18x-9}\)

\(\sqrt{1+x^2}-x=\frac{5}{\sqrt{1+x^2}}\)

\(\sqrt{4+x}+x=\sqrt{4+12x}\)