Question

Question #1d35a

Answer 1

`LHS=sin x/(1+cos x)+sin x/(1-cos x )`

`=(sin x(1-cos x)+sin x(1+cos x))/((1+cosx)(1-cosx))`

`=(sin x-sinxcos x+sin x+sinxcos x)/(1-cos^2x)`

`=(2sinx)/sin^2x=2/sinx=2cscx=RHS`