$$\lim_{x \to \infty}\left(x^{2} - y^{2}\right) = \infty$$ $$\lim_{x \to 0^-}\left(x^{2} - y^{2}\right) = - y^{2}$$ More at x→0 from the left $$\lim_{x \to 0^+}\left(x^{2} - y^{2}\right) = - y^{2}$$ More at x→0 from the right $$\lim_{x \to 1^-}\left(x^{2} - y^{2}\right) = 1 - y^{2}$$ More at x→1 from the left $$\lim_{x \to 1^+}\left(x^{2} - y^{2}\right) = 1 - y^{2}$$ More at x→1 from the right $$\lim_{x \to -\infty}\left(x^{2} - y^{2}\right) = \infty$$ More at x→-oo