First rewrite the problem so you get [tex]\sqrt \frac{1}{4}[/tex]
Then rewrite as [tex]\sqrt{1}\sqrt{4}[/tex]
any root of 1 is one so
1/[tex]\sqrt{4}[/tex]
1/[tex]\sqrt{ 2^{2}[/tex]
Pull terms out from under the radical, assuming positive real numbers.
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