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