\(N=\sqrt{4\sqrt{6}+8\sqrt{3}+4\sqrt{2}+18}\)
\(N=\sqrt{12+4+2+2\cdot2\sqrt{3}\cdot\sqrt{2}+2\cdot2\sqrt{3}\cdot2+2\cdot2\cdot\sqrt{2}}\)
\(N=\sqrt{\left(2\sqrt{3}\right)^2+2^2+\left(\sqrt{2}\right)^2+2\cdot2\sqrt{3}\cdot\sqrt{2}+2\cdot2\sqrt{3}\cdot2+2\cdot2\cdot\sqrt{2}}\)
\(N=\sqrt{\left(2\sqrt{3}+2+\sqrt{2}\right)^2}\)
\(N=2+2\sqrt{3}+\sqrt{2}\)