Answer
$i\sqrt{23}$
Work Step by Step
Factor the radicand so that one factor is a perfect square while the other factor is $-1$ to obtain:
$=\sqrt{23(-1)}$
RECALL:
(1) $\sqrt{ab} = \sqrt{a} \cdot \sqrt{b}$
(2) $\sqrt{-1} = i$
Use rule (1) above to obtain:
$=\sqrt{23} \cdot \sqrt{-1}$
Use rule (2) above to obtain:
$=\sqrt{23} \cdot i
\\=i\sqrt{23}$
