So the derivative wrt to the same order is something I know - but a problem has come up where I'm differentiating a quotient of these functions with different orders.

K_($\displaystyle \nu$+1)(z)/[tex]K_($\displaystyle \nu$)(z)

Differentiating wrt to $\displaystyle \nu$. Should I treat the the numerator as a constant? That was my first instinct, but I think that's probably incorrect. Anyone have any suggestions?