__How does function composition work?__x is only used as a place holder in the function. We can substitute in other values for x. When given the function composition , we take whatever is equal to and input it in for x in . This will give us the function composition. It is important to know that .

Make sure that the domain of the inner, first function is respected in the function composition.

Let’s go through an example step by step to help you better understand how to solve function compositions.

Here’s an example (click here):

Givenand ,find .

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1. Substitute for in

2. Substitute for in

3. Evaluate

Here’s another example (click here):

Last example (click here):

Function composition is very simple. My only piece of advice is to double check your work! It is so easy to have a simple calculation error that will cost you a point or two. Try your best to avoid this and double check your work. Practice a few tricky problems and you’ll be all set to move on from this topic.

Until next time,

Leah