Answer:
(a)
(b)P'(5)=-($4.54) Thousand
(c)P'(11)=-($2.10) Thousand
(d)The fifth Month
Step-by-step explanation:
Given the monthly profit model:
(a)We want to derive a model that gives the Marginal Profit, P' of the book.
We differentiate
using quotient rule.
Simplifying
We have derived a model for the marginal profit.
(b) After 5 months, at t=5
Marginal Profit=P'(5)
=-($4.54) Thousand of dollars
(c)Marginal Profit 11 Months after book release
=-($2.10) Thousand of dollars
(d) Since the marginal profit at t=5 is negative, after the 5th Month, the profit starts to experience a steady decrease.