文档介绍：Showing Why Math Matters
Gary Rockswold teaches algebra in context, answering the question,
“Why am I learning this?”
Going green
Many activities, such as driving a car, watching television, riding a
jet ski, or flying in an airplane, emit carbon dioxide into the air. A
commercial airliner, for example, emits 150 pounds of carbon
dioxide for each passenger who flies 240 miles. Understanding
our environmental impact on the is ing increasingly
important. Functions can be used to model and predict carbon
emissions. (See the Chapter 2 opener on page 76 and Example 4
from Section on page 81.)
How many songs will my iPod hold?
The number of songs that will fit on your iPod depends on
the size of its memory. We can use the concept of slope to
analyze memory requirements for storing music on iPods.
(See Example 2 from Section on page 49 to learn more.)
Determining sunset times
Whether we are traveling cross-country, driving a boat on a lake, or
designing a solar power plant, the time of sunset can be important. If we
know the sunset time on two different days, can we make predictions
about sunset times on other days? Using a linear function, we can often
make accurate estimates. (See Example 7 from Section on page 139.)
Shooting free throws
Is it better to shoot a free throw overhand or underhand?
Mathematics can be used to improve an athlete’s
performance. Learn how parabolas, the angle of
release, and the velocity of the basketball all play a role
in determining whether the ball goes through the hoop.
(See the Chapter 3 opener on page 169 to learn more.)
Modeling movement of weather
How do meteorologists know where a cold front will
be tomorrow? How do they know that one city will be
hit by a blizzard, and a city 100 miles away will get
only flurries? Scientists model weather systems and
make predictions by translating and transforming
graphs on a weather map. (Learn more in Section
on pages