Looks like simple algebra but can't do it.

The numerical vale of the following forms come equal. But I can't convert the 1st form into 2nd :-

1st. $\displaystyle ln {\frac{(\sqrt{1+x^2} - 1)(\sqrt{1+y^2} - 1)}{|xy|}}$

2nd. $\displaystyle -ln {\frac{(\sqrt{1+x^2} + 1)(\sqrt{1+y^2} + 1)}{|xy|}}$

Please show the steps.