Math — Probability Distributions

P(X=k) = \binom{n}{k}p^k(1-p)^{n-k}

P(X=k) = \frac{\lambda^k e^{-\lambda}}{k!}

f(x) = \frac{1}{\sigma\sqrt{2\pi}}\,e^{-\frac{(x-\mu)^2}{2\sigma^2}}

\sigma^2 = E[X^2] - (E[X])^2