Answer:
Explanation:
a) It can be convenient to use the square root function as one being defined only for values greater than or equal to some number. Here, we need to shift that function 3 units to the left, so its domain is [-3, ∞).

__
b) One way to put holes in a function is to put vertical asymptotes there. This function can be defined to have vertical asymptotes at x=2 and x=4 so those values are excluded from the domain.
