# HiSET: Math : Evaluate functions for inputs in their domains

## Example Questions

### Example Question #1 : Functions And Function Notation

Define and .

Evaluate .

The expression is undefined.

Explanation:

By definition,

,

so first, evaluate by substituting 2 for  in :

,

so evaluate through a similar substitution:

,

the correct response.

### Example Question #1 : Functions And Function Notation

Define functions and as follows:

Evaluate .

Undefined

Explanation:

By definition, . Evaluate by substituting 0 for in the definition of :

, so substitute 4 for in the definition of . Since 4 satisfies the condition , use the definition for those values:

,

the correct value.