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