Paper 4, Section I, 4E4 \mathrm{E}

Complex Analysis
Part IB, 2012

Let h:CCh: \mathbb{C} \rightarrow \mathbb{C} be a holomorphic function with h(i)h(i)h(i) \neq h(-i). Does there exist a holomorphic function ff defined in z<1|z|<1 for which f(z)=h(z)1+z2f^{\prime}(z)=\frac{h(z)}{1+z^{2}} ? Does there exist a holomorphic function ff defined in z>1|z|>1 for which f(z)=h(z)1+z2f^{\prime}(z)=\frac{h(z)}{1+z^{2}} ? Justify your answers.