Simplify x+yx−y−x−yx+y1+x−yx+y\frac{\frac{x+y}{x-y} - \frac{x-y}{x+y}}{1 + \frac{x-y}{x+y}}1+x+yx−yx−yx+y−x+yx−y.
y/xy/xy/x
x/yx/yx/y
y/x2y/x^2y/x2
1