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Section 1.3 : Radicals

6. Evaluate : \(\sqrt[3]{{ - 512}}\)

Hint : Recall that the easiest way to evaluate radicals is to convert to exponential form and then also recall that we evaluated exponential forms in the Rational Exponent section.
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All we need to do here is to convert this to exponential form and then recall that we learned how to evaluate the exponential form in the Rational Exponent section.

\[\sqrt[3]{{ - 512}} = {\left( { - 512} \right)^{\frac{1}{3}}} = \require{bbox} \bbox[2pt,border:1px solid black]{{ - 8}}\hspace{0.25in}\hspace{0.25in}\hspace{0.25in}{\mbox{because }}\hspace{0.25in}\,\,\,{\left( { - 8} \right)^3} = - 512\]