\(\sqrt{\left(19-6\sqrt{2}\right)}+\sqrt{\left(19+6\sqrt{2}\right)}\)
\(=\sqrt{\left(3\sqrt{2}-1\right)^2}+\sqrt{\left(3\sqrt{2}+1\right)^2}\)
\(=\left|3\sqrt{2}-1\right|+\left|3\sqrt{2}+1\right|\)
\(=\left(3\sqrt{2}-1\right)+\left(3\sqrt{2}+1\right)=6\sqrt{2}\)