Question 1189675
<pre>
Most of them are polynomials.

A polynomial cannot contain any denominator or roots that contain a
variable.  However, polynomials may contain denominators and roots as 
long as they do not contain any variables.

4, 8, and 9 are not polynomials because they contain denominators that 
contain variables.

The others are polynomials except that I can't tell about 7.  It depends on
whether you meant

{{{matrix(1,5, sqrt(2)x+4, OR, sqrt(2*x)+4, OR, sqrt(2*x+4))}}}

It would have been good if you had written parentheses to group together
what goes inside the square root, like this: √(2)x+4, √(2x)+4, or √(2x+4) 

The first one's root does not contain x, so it's a polynomial.
The other two's's roots do, so they're not polynomials.

Edwin</pre>