Answer
$-2i\sqrt 2$
Work Step by Step
Solve $-\sqrt{-8}$
As per square root property, we have $\sqrt{8}=\sqrt{2 \cdot 2 \cdot 2}=\sqrt{2^2} \cdot \sqrt 2= 2\sqrt 2$
Thus,
$-\sqrt{-8}=-2\sqrt 2\sqrt {-1}$
Since, $i^2=-1$ and $\sqrt {-1}=i$
Hence, $-\sqrt{-8}=-2i\sqrt 2$
