A person's fortune increases at a rate to the square of they're present wealth. If the person had one million dollars a year ago and has two million today then how much will the person be worth in six months?
Let the person's initial wealth be x dollars.
Given that the rate of increase of the pérson's wealth is equal to the square of the present amount,
==> dx/dt = x^2 ...(1)
where dx is the ...
Derivatives are applied to calculating interest.