Cube root

Summary

  • A cube root of a real number \(a\) is a solution to the equation

\[x^3=a\]

  • \(2\) is a cube root of \(8\) (as \(2^3=8\) ). \(-2\) is a cube root of \(-8\) (as \({\left( -2 \right)}^3=-8\) ).
  • For any real number \(a\) , the equation \(x^3=a\) has a unique real solution (which may be negative)
  • The cube root of \(a\) is denoted by \(\sqrt[3]{a}\) or \(a^{1/3}\) (which may be negative) .