Simplify

$\frac{1}{\sqrt{36}} - \sqrt{27} - \frac{1}{\sqrt{27}} - \sqrt{18} + \frac{1}{\sqrt{18}} - \sqrt{9}$

Begin by simplifying the radicals: ${1\over6}-3\sqrt{3}-{1\over{3\sqrt{3}}}-3\sqrt{2}+{1\over{3\sqrt{2}}}-3$

Then, rationalize the denominators: for example, ${1\over\sqrt{x}}={1\over\sqrt{x}}*{\sqrt{x}\over\sqrt{x}}={\sqrt{x}\over{x}}$:

${1\over{6}}-3\sqrt{3}-{3\sqrt{3}\over27}-3\sqrt{2}+{3\sqrt{2}\over18}-3$

Simplify the denominators, then combine like terms: ${1\over{6}}-3\sqrt{3}-{\sqrt{3}\over9}-3\sqrt{2}+{\sqrt{2}\over6}-3$

Put everyone under the same common denominator, 18: ${3\over{18}}-{54\sqrt{3}\over18}-{2\sqrt{3}\over18}-{54\sqrt{2}\over18}+{3\sqrt{2}\over18}-{54\over18}$

Combine like terms: ${-51-56\sqrt{3}-51\sqrt{2}\over18}$, I trust that you can split up the fraction if the answer specifies so.