4.7
November-23-14
8:04 PM
Ch 4.7 - Applications Involving Exponential Functions
Recall that exponential growth occurs for y=bx when the graph
__________ and the value of b is _____________
and exponential decay occurs when the graph ___________ and
the value of b is __________________
If the growth rate is given, add the decimal to 1 to find the base.
Ex 1
The population of a province is 35000 in 1996 and has grown at an
annual rate of 8%. What is the equation?
If the decay rate is given, subtract the decimal from 1 to find the
base.
Ex 2
A new car costs $24000, it loses 18% of it's value each year. What is
the equation?
The number to multiply your exponential by is the initial value.
Ex 3
Given the following data, determine the equation.
Year
0
1
2
3
4
Population 400 480 576 691 829
What is the population after a growth period of 30 months?
Ex 4
The half-life of a compound is the time it takes for the amount to
be half the original value. For 200g of polonium-210, with half-life
of 138 days is M(t) = 200(1/2)t/138
Determine the mass after 5 years.
MCR3U Page 1
Homework: page 261 #1, 3, 7, 9, 10, 12, 16
MCR3U Page 2