Find the general solution of the differential equation `(dy)/(dx)=(1+y^2)/(1+x^2)`.

Explanation

`dy / dx = ( 1 + x² ) / ( 1 + y² )`


`dy / ( 1 + y² ) = dx / ( 1 + x² )`


We know that , `∫ dp / ( 1 + p² )` = `tan⁻¹ p + C` , applying it here, we get,


Integrating both sides , we get,


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