(x⁻¹ + y⁻¹)² : (x+y)⁻² = (\frac{1}{x} + \frac{1}{y})² : \frac{1}{(x+y)²} = (\frac{x+y}{xy})² ⋅ (x+y)² = \frac{(x+y)⁴}{x²y²}
Ответ: \(\frac{(x+y)⁴}{x²y²}\)