find the value of the equation in the description given below

$\mathrm{Let} \sqrt{i} +\sqrt{-i}=x$$\mathrm{squaring},$$x^{2 }= (\sqrt{i} +\sqrt{-i}{)}^2= i +(-i) +2\sqrt{-i^2} =2\sqrt{1} \mathrm{as} i^2=-1$$x^2=2 \mathrm{hence} x =-\sqrt{2} \mathrm{or} \sqrt{2}$">