The law of demand

Why does demand slope downward?

The demand curve

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The demand curve slopes downward: higher price → lower quantity demanded

Individual vs. market demand

Movement along vs. shift of demand

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Shift right = increase in demand; Shift left = decrease in demand

Determinants of demand (demand shifters)

Substitutes and complements

Normal goods vs. inferior goods

The demand schedule

Demand function (linear)

Inverse demand function

Willingness to pay and the demand curve

AP exam tips for 1.4

Common mistakes

Key equations

Vocabulary