Question

Question #0ac31

Answer 1

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

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

`=(4sinx)/ (1 - sin^2 x)`

`=(4sinx)/ cos^2 x`

`=(2*2sinxcosx)/ cos^3 x`

`=2*sin(2x)sec^3 x=RHS`

proved