Precalculus : Pre-Calculus

Study concepts, example questions & explanations for Precalculus

varsity tutors app store varsity tutors android store

Example Questions

Example Question #1 : Piecewise Functions

Determine the value of  if the function is

Possible Answers:

Correct answer:

Explanation:

In order to determine the value of  of the function we set  

The value comes from the function in the first row of the piecewise function, and as such

Example Question #1 : Piecewise Functions

Determine the value of  if the function is



Possible Answers:

Correct answer:

Explanation:

In order to determine the value of  of the function we set  

The value comes from the function in the first row of the piecewise function, and as such

Example Question #1 : Piecewise Functions

For the function  defined below, what is the value of  when ?

Possible Answers:

3

8

7

0

-2

Correct answer:

8

Explanation:

Evaluate the function for . Based on the domains of the three given expressions, you would use , since  is greater than or equal to .

Example Question #1 : Special Functions

If  is the greatest integer function, what is the value of 

Possible Answers:

Correct answer:

Explanation:

The greatest integer function takes an input and produces the greatest integer less than the input. Thus, the output is always smaller than the input and is an integer itself. Since our input was , we are looking for an integer less than this, which must be  since any smaller integer would by definition not be "greatest". 

Example Question #981 : Pre Calculus

Which of the following is a point on the following function?

 

Possible Answers:

Correct answer:

Explanation:

One way to approach this problem would be to plug in each answer and see what works. However, I would be a little more strategic and eliminate any options that don't make sense.

Our y value will never be negative, so eliminate any options with a negative y-value.

Try (0,0) really quick, since it's really easy

The only point that makes sense is (5,83), therefore it is the correct answer

Example Question #982 : Pre Calculus

Evaluate:  

Possible Answers:

Correct answer:

Explanation:

Cancel the absolute value sign by separating the function  into its positive and negative counterparts.

Evaluate the first scenario.

Evaluate the second scenario.

The correct answer is:

Example Question #982 : Pre Calculus

If   , then what is the value of  when  ?

Possible Answers:

13

-13

-7

20

7

Correct answer:

13

Explanation:

We evaluate for 

Since the absolute value of any number represents its magnitude from  and is therefore always positive, the final answer would be 

Example Question #1 : Evaluate Functions

Given  and , evaluate .

Possible Answers:

Correct answer:

Explanation:

We are given two functions and asked to find f(h(7)).

I would begin by finding h(7)

Now that we know h(7), we go ahead and plug it into f(x).

So our final answer is simply 8.

Example Question #2 : Evaluate Functions

Solve the function.  

Possible Answers:

Correct answer:

Explanation:

Determine the domain of .

Multiply  on both sides of the equation to cancel the denominator and divide the equation  by ten.

Since the domain states that , the only possible answer is .

Example Question #1 : Evaluate Functions

Solve for :  

Possible Answers:

Correct answer:

Explanation:

Rewrite  so that the exponential variable is isolated.

Reconvert  to a similar base.  Use exponents to redefine the terms.

Since all terms are of the same base, use the property of log to eliminate the base on both sides of the equation.

Solve for .

Learning Tools by Varsity Tutors