$\sqrt{2}$ is a polynomial of degree

Factorise :

$x^{2}+9 x+18$

Find the zero of the polynomial in each of the following cases

$p(x)=3 x-4$

Write whether the following statements are True or False. Justify your answer.

$\frac{1}{\sqrt{5}} x^{\frac{1}{2}}+1$ is a polynomial

The value of the polynomial $5 x-4 x^{2}+3,$ when $x=-1$ is