\(\sqrt{18}-2\sqrt{32}+3\sqrt{50}-4\sqrt{8}\)
\(=3\sqrt{2}-8\sqrt{2}+15\sqrt{2}-8\sqrt{2}\)
\(=-5\sqrt{2}+15\sqrt{2}-8\sqrt{2}\)
\(=10\sqrt{2}-8\sqrt{2}\)
\(=2\sqrt{2}\)
\(\sqrt{18}-2\sqrt{32}+3\sqrt{50}-4\sqrt{8}\)
\(=3\sqrt{2}-4\sqrt{8}+15\sqrt{2}-4\sqrt{8}\)
\(=3\sqrt{2}+15\sqrt{2}-4\sqrt{8}-4\sqrt{8}\)
\(=18\sqrt{2}-8\sqrt{2}-8\sqrt{2}\)
\(=2\sqrt{2}\)