Ta có: \(\left(x+1\right)\left(x^2-x+1\right)-2x=x\left(x+1\right)\left(x-1\right)\)
\(\Leftrightarrow x^3+1-2x=x\left(x^2-1\right)\)
\(\Leftrightarrow x^3-2x+1=x^3-x\)
\(\Leftrightarrow x^3-2x+1-x^3+x=0\)
\(\Leftrightarrow1-x=0\)
hay x=1
Vậy: x=1