- Implicit Differentialon & Related Rates Course Packet on computing elasticity of demand using implicit differentiation The demand function for a certain brand of compact discs is given by P = -4x - 5x + 29 where p is the wholesale unit price in dollars and x is the quantity demanded each week, measured in units of a thousand. (a) Compute the price, p, when x = 2. Price, p dollars (b) Use implicit differentiation to compute the rate of change of demand with respect to price, p, when x = 2. Do not round your answer. Rate of change of demand, x'= thousands of units per dollar (c) Compute the elasticity of demand when x = 2. Do not round your answer, Elasticity of Demand =