Determining Components of an Exponential Function A doctor estimates that a particular patient is losing bone density at a rate
of 3% annually. The patient currently has a bone density of 1,500 kg/mg3. The doctor writes an exponential function to represent the situation. Which values should the doctor use for a and b in a function written in the form f(x) = abt, where f(x) represents the bone density after x years? 0 = b= Done Intro
a is the initial bone density, that is the bone density at 0 years, x is the number of years and b is any real value. For an exponential growth, b > 1 while for an exponential decay, b < 1.
Since the bone has a current density of 1,500 kg/m³, hence a = 1500.
The density is lost at a rate of 3% annually, therefore b = 100% - 3% = 97% = 0.97.
Therefore substituting the values of a and b into the function gives: