In this video, we solve an optimization problem of finding the shortest distance between two points where speed depends on the terrain. Watch out this time. The optimal solution may not be what you expected. This is lecture 4.9 (part 2/3) of the lecture series offered by Dr. Andrew Misseldine for the course Math 1210 - Calculus I at Southern Utah University, which can be found in the free textbook: https://github.com/emisseldine/Missel... Please post any questions you might have below in the comment field and Dr. Misseldine (or other commenters) can answer them for you. Please also subscribe for further updates.