+1222 $${\sqrt{-{\mathtt{2}}}} = {\mathtt{1.414\: \!213\: \!562\: \!373\: \!095}}{i}$$
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+70 The square root of -2 is irrational, meaning that you cannot simplify it into a regular number. If you have any more questions, feel free to ask! 
+33661 The square root of -2 doesn't exist in the domain of real numbers, but it does exist in the domain of complex numbers. It is i√2, where i is √(-1).
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+1222 $${\sqrt{-{\mathtt{2}}}} = {\mathtt{1.414\: \!213\: \!562\: \!373\: \!095}}{i}$$
