Classify the following polynomials as polynomials in one variable, two variables etc.
$x^{2}-2 x y+y^{2}+1$
Expand
$(11 x+18)(11 x-18)$
Find the following product :
$(2 x-y+3 z)\left(4 x^{2}+y^{2}+9 z^{2}+2 x y+3 y z-6 x z\right)$
Write the degree of each of the following polynomials
$x^{50}-1$
If $x+3$ is a factor of $x^{3}+12 x^{2}+a x+60$ then $a=\ldots \ldots \ldots$