The number of XM satellite Radio subscribers, in millions can be approximated by
f(t)=0.028(3.824)^(t-2001),where t is the year.
Find the instantaneous rate of change in the number of XM satellite radio subscribers in 2006 years.
I got f'(2006)=99.3968 ,but I don't know how to give the unit of that answer.
No! f represents the number of subscribers (in a particular year)Since f represents the number of subsribers per year
t does not just "represent time", t is measured in years.and t represents time we get
So df/dt is measured in "subscribers per year".The change in the number of subscribers per year.( in Millions)