Ответ:
- \(\frac{x^2-y^2}{(x+y)^2}=\frac{(x-y)(x+y)}{(x+y)^2}=\frac{x-y}{x+y}\).
- \(\frac{(x-y)^2}{x^2-y^2}=\frac{(x-y)^2}{(x-y)(x+y)}=\frac{x-y}{x+y}\).
- \(\frac{x^2-9}{x^2+6x+9}=\frac{(x-3)(x+3)}{(x+3)^2}=\frac{x-3}{x+3}\).
Ответ: а) \(\frac{x-y}{x+y}\); б) \(\frac{x-y}{x+y}\); в) \(\frac{x-3}{x+3}\).
