I think you have to first separate the integral:1/(1+v^2) + v/(1+v^2), so the integral of the first term is ArcTan (v) and for the integral of the second term i recommend you to do a change of variable:
y= 1+v^2 so dy= 2v and v= dy/2and then you substitute:v/(1+v^2) = (1/2)(dy/y) and the integral is (1/2) (In y)finally you plug in the initial variables: