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get rid of I in the result of an integral


Hi,

When I do Integrate[1/((1 + y)^2 Sqrt[-x^2 + y^2]), {y, x, Infinity},
  Assumptions -> x^2 < 1 && 1 > x > 0 && Element[x, Reals]]

I get

(-1 + x^2 - I Sqrt[1 - x^2] ArcSec[x])/(-1 + x^2)^2

and I would like the result expresed in terms of ArcSech[x] so that I 
does not appear.

I know I can tell Mathematica to do the replacement afterwards, but I 
want to show the result to a colleague who is not so familiar with 
mathematica, and if it were possible to get the result in one go just by 
adding some extra assumption or so, it would be more convincing.

Help will be appreciated. Best,

Ruth




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