Functions Operations: Function Notation and Evaluation

-  Functions are mathematical operations that assign unique outputs to given inputs.
-  Function notation is the way a function is written. It is meant to be a precise way of giving information about the function without a rather lengthy written explanation.
-  The most popular function notation is which is read "of ". Any letter can name a function. for example: , , etc.
-  To evaluate a function, plug in the input (the given value or expression) for the function’s variable (place holder, ).

Examples:
Example 1.  Evaluate: , find
Solution: Substitute with :

Then:

Example 2.  Evaluate: , find .
Solution: Substitute with :

Then:

Example 3.  Evaluate: , find .
Solution: Substitute with :
Then:

Example 4.  Evaluate: , find .
Solution: Substitute with :
Then: