6. Determine the domain and range for each function given. Explain where any restrictions come from.
a. f(x)= sqrt x + 5 – 4
b. f(x) = 1/2x^2 – 32
c. f(x) = 4/x^2 + 1
a. if that's sqrt(x+5), then domain is x >= -5
b. denominator cannot be zero, so all reals except -4,4
c. all reals