The function is $\"\"$ .

$\"\"$ .

The general form of polynomial function is $\"\"$ ,

where $\"\"$ are real numbers and $\"\"$ is a non negative integer.

The power of variable $\"\"$ is a non-negative integer, hence it is a polynomial function.

$\"\"$ is a polynomial function of degree $\"\"$ .

The function $\"\"$ is a polynomial function of degree $\"\"$ .