\(\sqrt{32}+\sqrt{50}-2\sqrt{8}+\dfrac{1}{3}\sqrt{18}\)
\(=\sqrt{4^2\cdot2}+\sqrt{5^2\cdot2}-2\cdot2\sqrt{2}+\dfrac{1}{3}\cdot\sqrt{3^2\cdot2}\)
\(=4\sqrt{2}+5\sqrt{2}-4\sqrt{2}+\dfrac{1}{3}\cdot3\sqrt{2}\)
\(=\left(4\sqrt{2}-4\sqrt{2}\right)+5\sqrt{2}+\sqrt{2}\)
\(=5\sqrt{2}+\sqrt{2}\)
\(=6\sqrt{2}\)