Ta có: \(x+y=2,5=\frac{5}{2}\)
\(\Rightarrow\left(x+y\right)^2=\frac{25}{4}\)
Ta có:
\(A=\frac{x}{y}+\frac{y}{x}\)
\(=\frac{x.x}{x.y}+\frac{y.y}{y.x}\)
\(=\frac{x^2}{xy}+\frac{y^2}{xy}\)
\(=\frac{x^2+y^2}{xy}\)
\(=\frac{\frac{25}{4}}{1}=\frac{25}{4}\)