Exponentials
Growth & Decay
Application 2
Write an equation to model bacterial growth. Assume the bacteria starts with 5 bacteria and doubles every 12 hours.
Step 1. Determine the initial value. The population starts at 5 bacteria.
Step 2. Write the rate as a growth factor. The population doubles.
for every 12 hours.
Step 3. Alter the exponent to include the doubling time of 12 hours. Recall that b is the common ratio as the input goes up by one and that roots can be rewritten as rational exponents. This input is going up by 12; therefore take the 12th root of 2 to simplify the expression.
Step 4. Write the equation.
