\(\rm 1\, - \,\frac{{{{\sin }^2}y}}{{1\, + \,\cos \,y}}\, + \,\frac{{1\, + \,\cos \,y}}{{\sin \,y}} - \frac{{\sin \,y}}{{1\, - \,\cos \,y}}\, = \,?\)
1
-1
2
1
3
sin y
4
cos y
\(\rm 1\, - \,\frac{{{{\sin }^2}y}}{{1\, + \,\cos \,y}}\, + \,\frac{{1\, + \,\cos \,y}}{{\sin \,y}} - \frac{{\sin \,y}}{{1\, - \,\cos \,y}}\, = \,?\)