If $m$ is the number of bits in the array, $k$ is the number of hash functions and we have $n$ entries, then the false positive probability upper bound can be approximated as:

$(1-{e}^{\frac{-kn}{m}}{)}^{k}$

It further states in the wiki article that:

"The number of hash functions, $k$, must be a positive integer. Putting this constraint aside, for a given $m$ and $n$, the value of $k$ that minimizes the false positive probability is:"

$k=\frac{m}{n}\mathrm{ln}2$

How can I find the $k$ value that minimizes the false positive function ?

$(1-{e}^{\frac{-kn}{m}}{)}^{k}$

It further states in the wiki article that:

"The number of hash functions, $k$, must be a positive integer. Putting this constraint aside, for a given $m$ and $n$, the value of $k$ that minimizes the false positive probability is:"

$k=\frac{m}{n}\mathrm{ln}2$

How can I find the $k$ value that minimizes the false positive function ?