3.1.7 Annual Fuel Cost, Instantaneous Rate of Change - Analytic Geometry and Calculus I

In this video, we work problem 108 from section 2.2 of the Larson Calculus text, 10th edition.
The problem requests that we find the annual fuel cost C, measured in dollars per year, as a function of gas mileage, x, measured in miles per gallon based on some estimates and assumptions of average number of miles driven per year and average price of gas per gallon.
Then we compute the derivative, graph C(x) and its derivative on Desmos.com, interpret the derivative as an instantaneous rate of change, and answer a related question.
Graph: www.desmos.com...