Answer
$\color{blue}{-2\sqrt[4]{2}}$
Work Step by Step
Factor the radicand so that one factor is a perfect fourth power to obtain:
$=-\sqrt[4]{16(2)}
\\=-\sqrt[4]{2^4(2)}$
Bring out the fourth root of the perfect fourth power factor to obtain:
$=\color{blue}{-2\sqrt[4]{2}}$
