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) .