2. Exponential Growth and Decay
Sign In
Use the general form of an exponential function, y=ab^x. Recall that b=1+r, where r is the rate of growth or decay.
y=35 000 (1.04)^x
y=a b^x In this formula, a is the initial value and b= 1+r, where r is the rate of change. To write the equation, we first need to define the variables. Let y be the annual salary, and let x be the number of years after the initial value. In this case, the initial value is a annual salary of $35 000. Since the salary increases 4 % each year, we have that r=0.04. y=35 000 ( 1+0.04)^x ⇕ y=35 000 ( 1.04)^x