Section 5.2 Continuity: Can't use arbitrary base b > 0
Your description of b a positive real number in Theorem 1 won't work
There is no exponential function f(x) = b^x for b=1. The function f(x) = 1^x is well-defined, but it is not an exponential function.
There is no logarithmic function f(x) = log_b(x) for b=1.