The population of a country changes at a rate proportional to the current size of the population and the prevailing economic situation. If the economy has a ten year cycle resulting in periods of immigration or emigration
where is the size of the population at time , measured in years, and , and are constants. Find an expression for the size of the population at any time.
Source: R.L. Rosenberg. (1984). Elementary Calculus: Course Notes. Ottawa, Canada: Holt, Rinehart and Winston. (Exercise 45: Question 2, p. 134)