\(M=\frac{\sqrt{6}\left(\sqrt{3}-\sqrt{2}\right)}{\sqrt{3}-\sqrt{2}}:\frac{1}{\sqrt{6}}=\sqrt{6}.\sqrt{6}=6\)
\(N=\frac{6\left(\sqrt{7}-1\right)}{\left(\sqrt{7}+1\right)\left(\sqrt{7}-1\right)}+\frac{\sqrt{7}}{7}=\frac{6\left(\sqrt{7}-1\right)}{6}+\frac{\sqrt{7}}{7}=\sqrt{7}-1+\frac{\sqrt{7}}{7}=\frac{8\sqrt{7}}{7}-1\)
\(O=\frac{\sqrt{3}\left(\sqrt{3}+2\right)}{\sqrt{3}}+\frac{\sqrt{2}\left(\sqrt{2}+1\right)}{\sqrt{2}+1}-\frac{2+\sqrt{3}}{\left(2-\sqrt{3}\right)\left(2+\sqrt{3}\right)}\)
\(=\sqrt{3}+2+\sqrt{2}-2-\sqrt{3}=\sqrt{2}\)