Let f(x) be the function

f(x) = x2 + 4x + 5

with domain D = {x| x 2}.

(a) Sketch the graph of the function f(x) with domain D.

(b) Since the function f(x) is decreasing on D, it has an inverse

function f 1(x). By solving the equation y = x2 + 4x+ 5 for x in

terms of y, where x 2, find a formula for the inverse function

f 1(x).

(c) Sketch the graph of the inverse function f 1(x) and state its

domain.