Answer:
(a) dD/dp = -6p - 4
(b) dD/dp = -64
Since the rate of change of demand is less than 1, the demand for the item is inelastic.
Explanation:
(a) D(p) = -3p^2 - 4p + 200
The rate of change of demand with respect to price is obtained by differentiating D with respect to p
dD/dp = -6p - 4
(b) dD/dp = -6p - 4
p = $10
dD/dp = -6(10) - 4 = -60 - 4 = -64
The rate of change of demand with respect to price is less than 1. This means that the demand for the item is inelastic. An inelastic demand is one in which there is little or no change in quantity demanded when price increases or wanes.