Which graphical condition guarantees that a relation represents a function of x?
01 - Functions and Mathematical Models Online Quiz Questions
Use this free practice quiz with 20 questions to review 01 - Functions and Mathematical Models, test your knowledge, and prepare for your next test or exam.
True or false: For any two functions f and g, the compositions (f∘g)(x) and (g∘f)(x) must be equal.
- A
True
- B
False
Let f(x)=3x−4. What is the value of f−1(20)?
Compared with the parent function f(x)=x, the function g(x)=x+4−1 is shifted and .
Select all statements that correctly describe restrictions used to determine the real-number domain of a formula.
- A
The denominator of a rational expression must be nonzero.
- B
The radicand of an even root must be nonnegative.
- C
The argument of a logarithm may be any real number.
- D
The argument of a logarithm must be positive.
True or false: In the model P(t)=P0bt, a base satisfying 0<b<1 represents exponential decay.
- A
True
- B
False
The temperature model is T(t)=12+3cos(6πt), where t is measured in months. What is the model's period?
- A
3 months
- B
6 months
- C
9 months
- D
12 months
A taxi charges a fixed fee of 4 dollars plus 2.50 dollars per mile, modeled by C(m)=4+2.50m. What is the cost for 6 miles?
For the height model h(t)=−16t2+64t+5, the meaningful time domain begins at and ends .
Assuming the logarithm arguments are positive, select all valid logarithm properties.
- A
logb(MN)=logbM+logbN
- B
logb(NM)=logbM−logbN
- C
logb(M+N)=logbM+logbN
- D
logb(Mp)=plogbM
What does the notation f−1(x) mean when f is one-to-one?
- A
The reciprocal of f(x)
- B
The derivative of f(x)
- C
The inverse function of f
- D
The negative of f(x)
In the continuous exponential model P(t)=P0ekt, explain the meaning of P0 and describe how the sign of k affects the model.
At which values of x is the tangent function undefined?
- A
x=kπ, where k∈Z
- B
x=2π+kπ, where k∈Z
- C
x=2kπ, where k∈Z
- D
All real x
Which test determines whether a graph represents a function of x?
- A
Every horizontal line intersects the graph at most once.
- B
Every vertical line intersects the graph at most once.
- C
The graph must cross both coordinate axes.
- D
The graph must be symmetric about the y-axis.
What is the domain of the function g(x) = (x + 1)/(x - 3)?
- A
All real numbers
- B
All real numbers except -1
- C
All real numbers except 3
- D
Only x greater than 3
True or false: In the composition (f composed with g)(x) = f(g(x)), the function f is applied before the function g.
- A
True
- B
False
What is the domain of h(x) = sqrt(x + 4) - 1?
- A
[0, infinity)
- B
[-4, infinity)
- C
(-4, infinity)
- D
(-infinity, -4]
For h(x) = sqrt(x + 4) - 1, enter the left endpoint of the domain as a number.
Which graphical test determines whether a function has an inverse that is also a function?
- A
The horizontal line test
- B
The vertical line test
- C
The denominator test
- D
The radicand test
The temperature model T(t) = 12 + 3 cos((pi/6)t) uses t in months. Enter its period in months as a number.