Find the general solution of the differential equation \(\frac{{dy}}{{dx}} = \frac{{1 + {y^2}}}{{1 + {x^2}}}\)
1
\({\tan ^{ - 1}}y = {\tan ^{ - 1}}x + c\)
2
\({\tan ^{ - 1}}y = 2{\tan ^{ - 1}}x + c\)
3
\({\tan ^{ - 1}}y = {\tan ^{ - 1}}\frac{x}{2} + c\)
4
\({y^2} = {x^2} + c\)