(<57 Go t I t? 5. a. If y o u h a v e 7 q t of paint, w h at do m ain a n d range are reasonable for
Problem 5?
b. Reasoning Why does it n o t m ake sense to have do m ain values less
th a n 0 or greater th a n 3 in P roblem 5?Lesso n Ch eck
Do yo u k n o w H OW?
- Identify the dom ain an d range of the relation
{ (—2,3), ( —1,4), (0, 5), (1, 6)}. R epresentthe relation
with a m apping diagram. Is the relation a function? - Is the relation in the graph show n
at th e right a function? Use the
vertical line test. - W hat is / ( 2 ) for the function
f(x) = 4x + 1? - The dom ain of f{x) = \x is { - 4 , - 2 , 0, 2 ,4 }. W hat is
the range?
MATHEMATICAL
Do y o u UN DERSTAN D? PRACTICES- Vocabulary Write y = 2x 4- 7 using function
notation. - C o m p a r e a n d C o n t r a s t You can use a m apping
diagram or th e vertical line test to tell if a relation is a
function. W hich m eth o d do you prefer? Explain. - Error Analysis A stu d e n t drew the
d ash e d line on th e g raph show n
a n d concluded th a t th e graph
re p resen te d a function. Is the
s tu d en t correct? Explain.
yX
0 i ■\Pr act i ce an d Pr o b l em - So l v i n g Ex er ci ses
. ^ 1 P ra c tic e
MATHEMATICAL
PRACTICESIdentify the domain and range of each relation. Use a mapping diagram to
determine whether the relation is a function.See Problem 1.- {(3, 7), (3, 8), (3, - 2 ) , (3, 4), (3,1)}
- {(0.04, 0.2), (0.2, 1), (1, 5), (5, 25)}
- { ( 6 , - 7 ) , ( 5 , - 8 ) , (1,4), (7, 5)}
- {(4, 2), (1, 1), (0, 0), (1, - 1 ) , (4, - 2 ) }
Use the vertical line test to determine whether the relation is a function.
13.See Problem 2.
- \ 2
15.
\ 2 y
\ y^ \
*- (^200) a
- Physics Light travels ab o u t 186,000 m i/s. The function d(t) = 186,0001
gives the distance d{t), in miles, th a t light travels in t seconds. How far does light
travel in 30 s? - Shopping You are buying orange juice for $4.50 p e r c o n tain e r a n d have a gift card
w orth $7. The function f(x) = 4.50x - 7 rep resen ts your total cost f{x) if you buy
x containers of orange juice a n d use th e gift card. How m u ch do you pay to buy
4 containers of orange juice?
See Problem 3.PowerAlgebra.com I L e s s o n 4 - 6 Fo r m a l i zi n g Re l at i o n s an d Fu n ct i o n s 271