finding domain and range of inverse functions?

Question

f^-1(x) = (x)^(1/2) - 3
D(0,oo)
R(-3,oo)

is this correct?

Answer 1

Almost. You would actually include the endpoints 0 and -3 (so you need to use a bracket instead of parentheses).
D = [0, infinity)
R = [-3, infinity)