Composite Functions

Find f(g(x))
g(x)=2x^2+4 and f(x)=x-2/4

Comments for Composite Functions

Average Rating starstarstarstarstar

Click here to add your own comments

Jul 24, 2010
Composite Functions
by: Karin

As the title states, this is known as a composite function.

We are asked to find f(g(x)) where:

f(x) = x-2/4 and g(x) = 2x^2+4

So, step 1 is to substitute the value (2x^2+4) for g(x):

f(g(x)) = f(2x^2+4) - Substitute 2x^2+4 for g(x)

Now, we know that we need to find f(2x^2+4) for the function: f(x) = x-2/4

Step 2: Substitute (2x^2+4) for x.

f(2x^2+4) = (2x^2+4)-2

Step 3: Simplify

2x^2+4-2 = 2x^2 +2
-------- -------
4 4

You can simplify further by dividing all terms by 2.

x^2 + 1 This is the final answer.

I hope this helps,

Click here to add your own comments

Join in and write your own page! It's easy to do. How? Simply click here to return to Students.

Need More Help With Your Algebra Studies?

Get access to hundreds of video examples and practice problems with your subscription! 

Click here for more information on our affordable subscription options.

Not ready to subscribe?  Register for our FREE Pre-Algebra Refresher and Solving Equations Unit!