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