If f(x) = log x – 4 and g(x) = 1/(x+4), for what value(s) of x is g(f(x)) undefined? Explain by making reference to the

If f(x) = log x – 4 and g(x) = 1/(x+4), for what value(s) of x is g(f(x)) undefined? Explain by making reference to the algebraic properties (do not graph).