Simplify (x2y−1)−2(x^2 y^{-1})^{-2}(x2y−1)−2
y2x4\frac{y^2}{x^4}x4y2
x4y2\frac{x^4}{y^2}y2x4
x−4y2x^{-4} y^2x−4y2
x4y−2x^4 y^{-2}x4y−2