In this episode of Full AP Course Review, we dive into Unit 6.1: Socially Efficient and Inefficient Market Outcomes. Learn the precise definition of social efficiency (MSB = MSC), why competitive markets achieve it without externalities, and how market failures like negative and positive externalities create deadweight loss through over- or underproduction. Master the graphs and concepts to ace AP Microeconomics exam questions on efficiency vs. equity.

• Socially efficient markets: MSB = MSC and maximized total surplus
• Competitive market benchmark: Equilibrium as the efficiency ideal
• Market failure basics: Overproduction and underproduction
• Negative externalities (e.g., pollution) and their graphs
• Positive externalities (e.g., gardens) and deadweight loss triangles
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