Chapter 7 Vocabulary (7-6)
◦3.) exponential function
7-6 EXPONENTIAL
FUNCTIONS
Algebra 1
Exponential Function
◦A function of the form 𝑦 = 𝑎 ∙ 𝑏 𝑥 , 𝑤ℎ𝑒𝑟𝑒 𝑎 ≠ 0, 𝑏 >
0, 𝑏 ≠ 1 𝑎𝑛𝑑 𝑥 𝑖𝑠 𝑎 𝑟𝑒𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟.
Identifying an exponential function.
◦ Ex. 1) Does the table or rule represent an exponential function?
◦ 1a.)
x
0
1
2
3
y
2
6
10
14
◦ 1b.) y = 3 ∙ 6𝑥
◦ 1c.) y = 2x
Evaluating an exponential function.
◦ Ex.2) A population of 75 foxes in a wildlife preserve quadruples in size every 15 years.
The function y = 75· 4𝑥 , where x is the number of 15 year periods, models the
population growth. How many foxes will there be after 45 years?
Graphing an exponential function.
1
◦ Ex. 3) What is the graph of 𝑦 = 4 ∙ 3𝑥 ?
Graphing an exponential model
◦ Ex. 4 ) A solid waste disposal plan proposes to reduce the amount of garbage each
person throws out by 2% each year. This year, each person threw out an average of
1500 lb of garbage. The function 𝑦 = 1500 ∙ 0.93𝑥 models the average amount of
garbage each person will throw out each year after x years. Graph the function.