Mathematics 30-1 Module 6

Module 6: Exponents and Logarithms

In Try This 5 you learned how to determine the equation of a function that models a given situation. You may have written the function as , where

c = 1.6
This value describes the rate of growth. The increase is 60%, so 1 + 0.60 = 1.6.
This value describes a horizontal stretch by a factor of 4. The increase occurs every 4 d.
a = 300
This value describes a vertical stretch by a factor of 300. The initial number of bacteria is 300.

For another example of using an exponential function to model a situation, read “Example 2” on pages 352 and 353 of the textbook. Notice while reading that this function has a horizontal asymptote. The horizontal asymptote helps determine the vertical translation of the function.

Self-Check 4

Complete “Your Turn” at the end of “Example 2” on page 353 of the textbook. Answer
Complete question 9 on page 356 of the textbook. Answer

Add the following terms to your copy of Glossary Terms:

exponential function
exponential growth
exponential decay

Add the following formula to your copy of Formula Sheet:

y = a(c)b(x−h) + k