Determine whether f is a function with the given domain and codomain. Explain why for those that are not functions. (R: set of real numbers, Z: a set of integers)

a) f: Z Z, where f(x) =

b) f: R R, where f(x) =

c) f: Z Z, where f(x) = any integer > x + 1

d) f: Z R, where f(x) = 1/x² - 3

e) f: Z Z, where f(x) = 1/x² - 3