# Thread: bound for complex nth derivative

1. ## bound for complex nth derivative

Hello,
I need help in the following problem:
Suppose f is holomorphic in U = {z: |z|<1} and $|f(z)|\leq \frac{1}{1-|z|}$ for all z in U. Find an inequality for the nth derivative of f at 0, i.e. $f^{(n)}(0)$
Thank you