Firstly we have to determine the domain of the function 

The domain of the function is the set of values for which the function is real and defined.
In the function 
 we can clearly observe that for the negative values of x , the value of y will not be real.
 we can clearly observe that for the negative values of x , the value of y will not be real.
So, the domain for this function is 
 or
 or 
 .
.
The second function is 

In this function we can clearly observe that for the values of x less than -3, the function is not real.
So, the domain for this function is 
 or
 or 
