# Ln

$$\ln \!=\!\log_{\mathrm e}\!=\!\mathrm{Log}$$ is name of natural logarithmic function, that appears as solution of the differential equation

$$\displaystyle \ln'(z)=\frac{1}{z}$$

or as inverse function, id est, the minus first iteration of natural exponential exp,

$$\ln(z)=\exp^{-1}(z)$$