Consumer theory
Perfect substitutes
Optimal choice when indifference curves are straight lines — a corner solution — with a companion bus-versus-metro exercise.
To go with the lectures
Problems
Problems to accompany the YouTube lectures. Each PDF has one solved problem with a video walkthrough and one exercise without a solution.
Consumer theory
Perfect complements
Goods used in fixed proportion, so the optimum sits at the kink — with a dal-and-rice exercise.
Consumer theory
Cobb–Douglas
Interior optimal choice with smooth and convex indifference curves — demand is a constant share of the budget — with a Stone–Geary exercise.
Consumer theory
Hybrid preferences
Demand as a correspondence, from a utility that is part substitutes and part complements. With a rice-and-beans exercise.