\[ \left (x^2-1\right ) y'(x)^2-1=0 \] ✓ Mathematica : cpu = 0.0156761 (sec), leaf count = 41
\[\left \{\left \{y(x)\to c_1-\log \left (\sqrt {x^2-1}+x\right )\right \},\left \{y(x)\to c_1+\log \left (\sqrt {x^2-1}+x\right )\right \}\right \}\]
✓ Maple : cpu = 0.026 (sec), leaf count = 33
\[ \left \{ y \left ( x \right ) =-\ln \left ( x+\sqrt {{x}^{2}-1} \right ) +{\it \_C1},y \left ( x \right ) =\ln \left ( x+\sqrt {{x}^{2}-1} \right ) +{\it \_C1} \right \} \]