Câu trả lời:

\(A=\frac{\sqrt{18}}{\sqrt{8}}+\frac{\sqrt{8}}{\sqrt{50}}=\frac{\sqrt{18}.\sqrt{50}+\sqrt{8}.\sqrt{8}}{\sqrt{8}.\sqrt{50}}=\frac{\sqrt{900}+\sqrt{64}}{\sqrt{400}}=\frac{30+8}{20}=\frac{38}{20}=\frac{19}{10}\)