Question

GIẢI PT:

\(x^3-x^2-x=\dfrac{1}{3}\)

Answer 1

\(x^3-x^2-x=\dfrac{1}{3}\)

\(\Leftrightarrow3\left(x^3-x^2-x\right)=1\)

\(\Leftrightarrow3x^3-3x^2-3x=1\)

\(\Leftrightarrow4x^3-x^3-3x^2-3x=1\)

\(\Leftrightarrow4x^3=x^3+3x^2+3x+1\)

\(\Leftrightarrow4x^3=\left(x+1\right)^3\)

\(\Leftrightarrow x=\dfrac{x+1}{\sqrt[3]{4}}\)

\(\Leftrightarrow x=\dfrac{1}{\sqrt[3]{4}-1}\)