Answer
The answer is perfectly reasonable by a linear approximation shown below...
Work Step by Step
The slope of $\sqrt {2x}$ near $x = 2$ is about $1/2$ as
$$f'(x) = 1/\sqrt{2x}$$
Thus, if x were to increase by $0.01$, then $y$ would increase by $0.005$
$\sqrt{2*2}+0.005= 2.005$
