Simplify f(x)=2 square root of 0

$f (x) = 2 \sqrt{0}$

Rewrite $0$ as $0^{2}$ .

$f (x) = 2 \sqrt{0^{2}}$

Pull terms out from under the radical, assuming positive real numbers.

$f (x) = 2 \cdot 0$

Multiply $2$ by $0$ .

$f (x) = 0$