Integrating a function f(x) I am a bit confused about an integration that I came across. $f(x)$ is a function and we are integrating:
$$\int_0^t {df(x)\over f(x)} = \ln \left({f(t)\over f(0)}\right)$$
I am a confused because I was expecting an answer like $\ln(f(x)) - \ln(f(0))$

These are in fact equivalent due to the log rule $$\ln b - \ln a = \ln \frac{b}{a}$$
