$\"\"$

The function is $\"\"$ . \ \ In rational functions denominator cannot be equal to zero because if it is equal to zero the function would be undefined. \ \

$\"\"$

$\"\"$ and $\"\"$

$\"\"$ and $\"\"$ .

So the domain of the function $\"\"$ is $\"\"$ .

$\"\"$

The domain of the function $\"\"$ is $\"\"$ .