You have a minor typo in your intended result, but it is obtained by using the quotient rule:
For the function you cite, we also need:
Having trouble finding the answer to this question:
Let Y = cosx + sinx / cosx - sinx
The answer is supposed to be (cosx - sinx)(-sinx + cosx)-(cosx + sinx)(-sinx - sinx) / (cosx-sinx)^2 which can be simplified further
But I have no idea how this is gotten Please Help!