Domains and Ranges

Domain: are all numbers in "X" 

Range: Are all numbers in "Y" 

This table will help you to recognize the type of the domain and the range in different functions:

Here are some tips that are very useful.

If the degree of P(X) is equal to the degree on Q(x)

If the degree of P(X) is lower to the degree on Q(x)

If the degree of P(X) is lower to the degree on Q(x)

The rationals is need to know one simple a rule,the denominator should never be  0. (Domain)

The radicals also have a rule, it should never give you a negative number inside the root.

To have a range, you need to get the (X).

The rationals is need to know one simple a rule,the denominator should never be  0. (Range), exactly the same rule of Domain.

To locate a domain and a range in a table.

The domain values ​​are the farthest from the(X) axis. The range values are the farthest to the (Y) axis. 

In case if you get confused.