\int{x^2-1}/{(x^2+1)\sqrt{x^4+1} dx =

Correct Answer is : 1√2sec−1(x2+1√2x) + c

\sec^{-1}(\frac{x^2+1}{\sqrt2 x}) + c

1/\sqrt2 \sec^{-1}(\frac{x^2+1}{\sqrt2 x}) + c