Here, the chain rule is key: If {{MATH_12}} is written in terms of {{MATH_13}}, and we are given {{MATH_14}}, then it is easy to find {{MATH_15}} using the chain rule: {{MATH_16}} {{MATH_17}} In many cases, particularly the interesting ones, our functions will be related in some other way. Nevertheless, in each case we'll use the chain rule to help us find the desired rate. In this section, we will work several abstract examples in order to emphasize the mathematical concepts involved. In each of the examples below, we will follow essentially the same plan of attack: