Let f: R [0, +) and g : [0, +) (-, 0] be the functions defined by f(x) = x and g(x):= -x. (a) Explain why fog makes sense (can be defined) even though the codomain of g is not equal to the domain of f. (b) Write down the domains and codomains of fog and gof, and find explicit formulas for these functions. (c) Is g the inverse of f? Explain your answer.