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