# Idea If $f(x)$ is continuous at $x$, then the [[probability density|probability density function]] is the derivative of the [[cumulative distribution function]]. The [[cumulative distribution function|CDF]] of a continuous random variable $X$ can be expressed as the integral of its [[probability density|probability density function]] $f_X$ as follows: $ F_{X}(x)=\int_{-\infty}^{x} f_{X}(t) d t $ Make a gif that slides... ![[s20220606_005428.png]] # References