Question 775094
(1) The base function of f(x) = √(4-x) is the function g(x) = √x.  The domain of this function is {x ∈ R: x ≥ 0}.
 
(2) The function h(x) = √(4+x) indicates a translation of the base function, g(x), four units to the left.  Therefore, the domain of h(x) is {x ∈ R: x ≥ -4}.
 
(3) The original function f(x) = √(4-x) indicates a reflection along the y-axis.  Therefore, the domain of f(x) is {x ∈ R: x ≤ 4}.