$\begin{array}{1 1} \log\mid(x+1)+\sqrt{x^2+2x+2}\mid+c \\ \log\mid(x+1)-\sqrt{x^2+2x+2}\mid+c \\ \log\mid(x-1)-\sqrt{x^2+2x+2}\mid+c \\ \log\mid(x+1)-\sqrt{x^2-2x+2}\mid+c\end{array} $