how to set up the difererntial equation...?
We are told that:
$\displaystyle \frac{d}{dt}P(t)=0.04 P(t) + 520$
The first term on the right is the rate of increase in value at time $\displaystyle t$ due to the interest, and the second term on the right is the rate of increase in value due to savings. The unit of time here is 1 year.
CB