Rút gọn P= $($$\frac{\sqrt{x}-1}{\sqrt{x}+1}$$-$$\frac{\sqrt{x}+1}{\sqrt{x}-1}$$)$.$($$\frac{1}{2\sqrt{x}}$$-$$\frac{\sqrt{x}}{2}$$)$$^{2}$
Rút gọn P= $($$\frac{\sqrt{x}-1}{\sqrt{x}+1}$$-$$\frac{\sqrt{x}+1}{\sqrt{x}-1}$$)$.$($$\frac{1}{2\sqrt{x}}$$-$$\frac{\sqrt{x}}{2}$$)$$^{2}$