Đk x≥−1
⇔√x4+1−√x3+1+√x2+1−√x+1=0⇔x4−x3√x4+1+√x3+1+x2−x√x2+1+√x+1=0
\Leftrightarrow \left[ {\begin{matrix} x^2-x=0\\ \frac{x^2}{\sqrt{x^4+1}+\sqrt{x^3+1}}+\frac1{\sqrt{x^2+1}+\sqrt{x+1}}=0(vônghiệm) \end{matrix}} \right.
\Leftrightarrow \left[ {\begin{matrix} x=0(tm)\\ x=1(tm)\end{matrix}} \right.