$\begin{array}{1 1} x\tan^{-1} x- \frac{1}{2} \log|1+x^2|+c \\ x\tan^{-1}x+ \frac{1}{2} \log|1+x^2|+c \\ x\tan^{-1}x- \frac{1}{2} \log|1-x^2|+c \\ x\tan^{-1}x+ \frac{1}{2} \log|1-x^2|+c \end{array} $
