b. \( \sqrt{(-x)^{6}}= \)

To solve \( \sqrt{(-x)^{6}} \), we can simplify the expression under the square root. Since raising a negative number to an even power results in a positive number, we have \( (-x)^{6} = (x^{6}) \). Thus, \( \sqrt{(-x)^{6}} = \sqrt{x^{6}} \), which simplifies to \( |x^{3}| \) because the square root calculates the principal (non-negative) root. Alternatively, if you ignore the absolute value, you might think \( \sqrt{x^{6}} = x^{3} \), but remember, \( |x^{3}| \) accounts for all potential values of \( x \). So the final answer is \( |x^{3}| \).