(1-(sin(x)^2))/(1+(sin(x))
Does this simplify any further?
1 - sin(x)^2 factors as a difference of two squares thusly....(1 + sin(x)) (1 - sin(x))
So we have.....
[(1 + sin(x)) (1 - sin(x))] / (1 + sin(x)) = 1 - sin(x)