Download Unit 1 Test Review

Unit 1 Test Review
Which of the following relations are
functions?
• y=7
• x=7
• x+y=7
Answer
• y= 7 is a function – horizontal line will pass the vertical line test.
• x =7 is not a function – for the x-value of 7, there are multiple yvalues
• x + y =7 is a function - for each value of x, there is a unique value of y
The distance D(t) traveled by a jaguar is a
function of time (t).
• A) Express the following statement using function notation. The
jaguar had traveled 150 miles after 3 hours.
• B) What does D(1)=50 mean in the context of the problem?
• C) What does D(k) = m mean in the context of the problem?
Answer
• A) D(3) = 150
• B) The jaguar had traveled 50 miles after one hour.
• C) The jaguar had traveled m number of miles after k hours.
Find 2 possible solutions to the graph of the
equation x – 3y + 1 = 4.
Answer
• Any ordered pair that satisfies the equation is a solution.
• Possible answers are (-3, -2), (0, -1), (3, 0), (6, 1)….
Fill in the missing value in the chart.
Answer
• F(9) = 54
Lauren keeps records of the distances she travels
in a taxi and what she pays:
a) What is the independent variable?
b) What is the dependent variable?
c) _____________ is a function of _____________________
d) Write an equation, in function notation, to represent the taxi fare for
the distance traveled.
e) Interpret the meaning of F(3)=8.25.
Answer
• a) number of miles
• b) taxi fare
• c) Taxi fare is a function of distance traveled in miles.
• d) F(d) = 2.25d +1.50
• e) Lauren’s taxi fare will cost $8.25 if her destination was 3 miles.
How would you recognize a linear function?
Answer
• Graphically – it’s a line
• Numerically – it has a constant rate of change
• Symbolically – equation can be rewritten in slope-intercept form
How would you recognize a quadratic
function?
Answer
• Graphically – it’s a parabola
• Numerically – same y-value for 2 different domain
• Symbolically – a variable x is taken to the power of 2
How would you recognize an exponential
function?
Answer
• Graphically – non-linear function that increases or decreases
• Numerically – it has a common ratio
• Symbolically – the variable x is used as an exponent
Your grandma is buying candy bars for Halloween.
Assume that there are a total of 80 kids in the
neighborhood and each candy bar costs $0.50.
• A) What is the domain in the context of the problem?
• B) What is the range in the context of the problem?
• C) What are some restrictions on the domain and range?
Answer
• A) Domain is all whole numbers between 0 and 80.
• B) Range is $0 to $40, in increments of fifty cents.
• C) The values in the domain can’t be decimal, fraction, or negative
since we are dealing with number of children. The range has to be 0
or a positive value up to $40 to represent the cost. Since you can’t
purchase a fraction of a candy bar, the cost has to increase by fifty
cents. For example, your grandma can’t spend $7.25.