Chapter 6 - Radical Functions and Rational Exponents - 6-1 Roots and Radical Expressions - Practice and Problem-Solving Exercises - Page 365: 46

sometimes true

The given statement is true when $x$ is positive. Example: $\sqrt{2^6} = \sqrt{64} = 2^3 = 8.$ However, the statement is false when $x$ is negative. $\sqrt{(-2)^6} = \sqrt{64} = 8$, but $x^3=(-2)^3 = -8.$ Therefore, the statement is sometimes true.