The slope of normal at any point \( (x,y) \), \( x>0 \), \( y>0 \) on the curve \( y=y(x) \) is given by \( \frac{x^2}{xy-x^2y^2-1} \). If the curve passes through the point \( (1,1) \), then \( e \cdot y(e) \) is equal to:
\( \frac{1-\tan(1)}{1+\tan(1)} \)
\( \tan(1) \)
\( 1 \)
\( \frac{1+\tan(1)}{1-\tan(1)} \)