ĐK: x>=1
\[\begin{array}{l}
\sqrt {x - 1} + \sqrt {{x^3} + {x^2} + x + 1} - 1 - \sqrt {(x - 1)({x^3} + {x^2} + x + 1)} = 0\\
\sqrt {x - 1} (1 - \sqrt {{x^3} + {x^2} + x + 1} ) - (1 - \sqrt {{x^3} + {x^2} + x + 1} ) = 0\\
(\sqrt {x - 1} - 1)(1 - \sqrt {{x^3} + {x^2} + x + } 1) = 0\\
\to \sqrt {x - 1} = 1\\
\end{array}\] \[\begin{array}{l} \to x = 2\\\end{array}\]
hoặc \[\begin{array}{l}
\sqrt {{x^3} + {x^2} + x + 1} = 1\\
\to x = 0(loai)
\end{array}\]
