This document discusses bivariate transformations and calculating probabilities of transformed random variables. It introduces calculating the probability that the maximum and minimum of iid random variables fall in a given range using the distribution function technique. This involves finding the probability that all variables are individually greater than some value a to find the probability the minimum is greater than a. Similarly, the probability the maximum is less than a involves finding the probability all variables are individually less than a. It also discusses finding the joint distribution of the maximum and minimum using a double integral over the joint density function.