Question

Please help I'm running out of time

Answer 1

So remember that $\sqrt{x} \sqrt{y} = \sqrt{xy}$ so $\sqrt{-18} = \sqrt{9} \sqrt{-1} \sqrt{2} =3i\sqrt{2}$ $\sqrt{-2} = \sqrt{-1} \sqrt{2} =i\sqrt{2}$ $i\sqrt{2}+3i\sqrt{2}=\sqrt{2}(i+3i)=\sqrt{2}(4i)=4i\sqrt{2}$ answer is second one or $4\sqrt{2}i$