\(=\dfrac{6\left(\sqrt{2}-\sqrt{3}-3\right)}{5-2\sqrt{6}-9}=\dfrac{6\left(\sqrt{2}-\sqrt{3}-3\right)}{-4-2\sqrt{6}}\\ =\dfrac{3\left(3+\sqrt{3}-\sqrt{2}\right)}{2+\sqrt{6}}=\dfrac{\left(9+3\sqrt{3}-3\sqrt{2}\right)\left(\sqrt{6}-2\right)}{2}\\ =\dfrac{9\sqrt{6}-18+9\sqrt{2}-6\sqrt{3}-6\sqrt{3}+6\sqrt{2}}{2}\\ =\dfrac{9\sqrt{6}+15\sqrt{2}-12\sqrt{3}-18}{2}\)