Natural logarithm

red: natural logarithm

The natural logarithm, $\ln(x)$ is the inverse of the function $e^{x}$. In other words, if $y=e^{x}$, we define $\ln(y)=x$.

The natural logarithm has some interesting properties that follow from the multiplicative properties of $e^{x}$. The natural logarithm is also particularly useful in calculating interest.