College Algebra 7th Edition

$|x|$
RECALL: (i) $\sqrt[n]{a^n} = |a|$ when $n$ is even (ii) $\sqrt[n]{a^n} = a$ when $n$ is odd The given radical has n=4, which is even. Use rule (i) above to obtain: $\sqrt[4]{x^4}=|x|$