What are two methods for calculating elasticity of demand?

Two common methods for calculating elasticity of demand are the percentage change method and the point elasticity method. The percentage change method involves dividing the percentage change in quantity demanded by the percentage change in price. The point elasticity method, on the other hand, uses calculus to calculate elasticity at a specific point on the demand curve, typically by taking the derivative of the demand function and multiplying it by the price-quantity ratio. Both methods provide insight into how sensitive consumers are to price changes.