A(t)

is the amount of the investment at time t for the case of continuous compounding, write a differential equation satisfied by
A(t).

A(t) = Pe^nrt

A' = nrPe^nrt

dy/dx = nr y

To find the differential equation satisfied by A(t) for continuous compounding, we can use the formula for continuous compound interest.

The formula for continuous compound interest is given by:
A(t) = P * e^(rt)

Where:
A(t) is the amount of the investment at time t
P is the principal (initial investment)
e is the base of the natural logarithm (approximately equal to 2.71828)
r is the annual interest rate
t is the time in years

Now, let's differentiate both sides of the equation with respect to time (t):

(dA(t))/(dt) = (d/dt)(P * e^(rt))

Using the product rule of differentiation, we can differentiate the right side of the equation:

(dA(t))/(dt) = P * (d/dt)(e^(rt))

Now, let's find the derivative of e^(rt):

(d/dt)(e^(rt)) = re^(rt)

Substituting this derivative back into the equation, we have:

(dA(t))/(dt) = P * re^(rt)

Therefore, the differential equation satisfied by A(t) for continuous compounding is:

(dA(t))/(dt) = P * re^(rt)