Algebra II : Function Notation

Study concepts, example questions & explanations for Algebra II

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Example Questions

Example Question #2 : How To Use The Quadratic Function

Given , find .

Possible Answers:

Correct answer:

Explanation:

Plug in a for x:

Next plug in (a + h) for x:

Therefore f(a+h) - f(a) =  .

 

Example Question #32 : Algebraic Functions

Solve for  when .

Possible Answers:

Does not exist

Correct answer:

Explanation:

Plug 3 in for x:

 

Simplify:

 = 

 = 5

 

Example Question #11 : Function Notation

What is of the following equation? 

Possible Answers:

Correct answer:

Explanation:

To complete an equation with a  function, plug the number inside the parentheses into the equation for  and solve algebraically.

In this case the 

Square the 7 and multiply to get 

Add the numbers to get the answer .

Example Question #141 : Functions And Graphs

Possible Answers:

Correct answer:

Explanation:

Example Question #141 : Functions And Graphs

Possible Answers:

Correct answer:

Explanation:

Example Question #13 : Function Notation

If , find .

Possible Answers:

Correct answer:

Explanation:

If  then  can be rewritten as . Therefore, . Subtracting  from both sides of the eqauation gives .

Example Question #14 : Function Notation

Evaluate the function for .

Possible Answers:

Correct answer:

Explanation:

To solve for the value of the function at , simply plug in the value  in place of every . By doing this, you will be left with the equation:.

Another way to go about the problem is first simplifying the expression so that like terms are collected, so . Then to find , simply plug in the value  in place of every .  By doing this, you will be left with the equation:.

Example Question #11 : Function Notation

Given  and , find .

Possible Answers:

Undefined

Correct answer:

Explanation:

Given f(x) and g(x), find f(g(5))

This type of problem can look intimidating depending on how it is set up. What it is asking is for us to plug g(x) into f(x) everywhere we see an x, and then to plug in 5 everywhere we still have an x. It gets a little cumbersome if approached all at once:

This looks a bit unwieldy, but this problem can be approached easily by looking at it in layers.

First, find g(5)

.

Next, plug that 15 into f(x).

So our answer is:

Example Question #16 : Function Notation

If  and , what is ?

Possible Answers:

Correct answer:

Explanation:

We start by replacing all the 's in  with the entire function of :

We then FOIL the first term:

And we collect all the like terms (the constants in this case):

Example Question #17 : Function Notation

What is

 ?

Possible Answers:

Correct answer:

Explanation:

To find the composition of two functions, substitute the second equation in to the first function.

Therefore, 

 

   

and 

Thus,

 .

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