show the answer for given the demand curve of the monopolist q=30-0.3p,and given the cost function c=2q2 +20q+10, a. find profit maximizing level of output and price
revenue r = price * quantity = pq
profit = revenue - cost = q(30-q)/0.3 - (2q^2+20q+10)
= -16/3 q^2 + 80q + 10
The maximum profit occurs when q = 7.5