Rút gọn biểu thức:

\(A = \frac{{{{\left( {\sqrt x + \sqrt y } \right)}^2} - 4\sqrt {xy} }}{{\sqrt x - \sqrt y }} - \frac{{x\sqrt y + y\sqrt x }}{{\sqrt {xy} }}\) (với x, y > 0, x ≠ y).

\(A = \frac{{{{\left( {\sqrt x + \sqrt y } \right)}^2} - 4\sqrt {xy} }}{{\sqrt x - \sqrt y }} - \frac{{x\sqrt y + y\sqrt x }}{{\sqrt {xy} }}\)

\(A = \frac{{x + 2\sqrt {xy} + y - 4\sqrt {xy} }}{{\sqrt x - \sqrt y }} - \frac{{\sqrt {xy} \left( {\sqrt x + \sqrt y } \right)}}{{\sqrt {xy} }}\)

\(A = \frac{{x - 2\sqrt {xy} + y}}{{\sqrt x - \sqrt y }} - \left( {\sqrt x + \sqrt y } \right)\)

\(A = \frac{{{{\left( {\sqrt x - \sqrt y } \right)}^2}}}{{\sqrt x - \sqrt y }} - \left( {\sqrt x + \sqrt y } \right)\)

\(A = \sqrt x - \sqrt y - \sqrt x - \sqrt y = - 2\sqrt y \)