Simplify, if possible. \[ \sqrt{-12} \] \[ \sqrt{-12}= \] (Simplify your answer. Type an exact answer, using radicals and $i$ needed.)

Step 1 ：The square root of a negative number is not a real number, but it can be expressed as a complex number. The square root of -1 is represented as 'i' in complex numbers.

Step 2 ：So, the square root of -12 can be written as the square root of 12 times the square root of -1, which is 'i'.

Step 3 ：The square root of 12 can be simplified further by factoring it into 4 and 3, where the square root of 4 is 2.

Step 4 ：So, the square root of -12 is 2 times the square root of 3 times 'i'.

Step 5 ：Final Answer: \(\sqrt{-12} = \boxed{2\sqrt{3}i}\)